IDS Flashcards

Question

A 30/F came into the ER due high spiking fever with associated abdominal pain of 1 week duration. She self-medicated with ciprofloxacin on the 4th day of her symptoms with no relief. A day prior to consult, the patient developed faint, salmon-colored blanching, maculopapular rash on the trunk and chest which prompted consult at the OPD. Which of the following specimens is the best option for culture studies to demonstrate the causative organism? (HPIM 20th ed. C160 P1176) a. Bone marrow b. Blood c. Stool d. Skin biopsy

Answer 1

The correct answer is: Bone marrow

Answer 2

The correct answer is: Ceftriaxone 2g IV q24

Answer 3

The correct answer is: Exposure to contaminated soil

Answer 4

The correct answer is: Atrial fibrillation

Answer 5

The correct answer is: Doxycycline 200mg once weekly, 1-2 days before exposure and continued until the end of the trip

Answer 6

The correct answer is: Initiate dialysis

Answer 7

The correct answer is: P. falciparum

Answer 8

The correct answer is: Mefloquine

Answer 9

The correct answer is: Urine output of < 0.5cc/kg/hr

Answer 10

The correct answer is: IV fluids of 20ml/kg in the first 3 hours

Answer 11

The correct answer is: Granuloma formation around the deposited eggs

Answer 12

The correct answer is: Praziquantel 60 mg/kg PO in 3 divided doses for 1 day

Answer 13

The correct answer is: Blood pressure

Answer 14

The correct answer is: TIG + Tetanus Toxoid

Answer 15

The correct answer is: Nuchal biopsy

Answer 16

The correct answer is: RIG and rabies vaccine

Answer 17

The correct answer is: Watery diarrhea may also be a presenting symptom

Answer 18

The correct answer is: Pulmonary tuberculosis

Answer 19

The correct answer is: Needle-sharing during injection drug use

Answer 20

The correct answer is: p24 antigen capture assay

Answer 21

The correct answer is: Pneumocystis jirovecii

Answer 22

The correct answer is: 4 weeks

Answer 23

The correct answer is: Repeat history and physical examination

Answer 24

The correct answer is: 6 weeks

Answer 25

The risk of transmission and of subsequent acquisition of M. tuberculosis infection is determined mainly by exogenous factors: • Probability of contact with a person who has an infectious form of TB • Intimacy and duration of that contact • Degree of infectiousness of the case • Shared environment in which the contact takes place The risk of developing disease after being infected depends largely on endogenous factors: • Individual’s innate immunologic and nonimmunologic defenses • Level at which the individual’s cell-mediated immunity is functioning. The correct answer is: Innate immunologic and non-immunologic defenses

Answer 26

The correct answer is: 30 year old nurse with cough of 7 days duration

Answer 27

The correct answer is: Direct sputum smear microscopy

Answer 28

The correct answer is: At least 2 out of 3 sputum smear positive should be present to be considered smear positive

Answer 29

The correct answer is: PTB, Bacteriologically confirmed, Smear positive

Answer 30

CHEST X-RAY FOR PTB DIAGNOSIS Patient with CXR findings suggestive of PTB with or without symptoms is a Presumptive TB A single CXR film cannot accurately confirm active PTB by this modality alone No radiologic findings considered specific for active TB. Clinical correlation, together with bacteriologic confirmation, is required to assess activity BEFORE initiation of treatment A good quality CXR film is needed to initially guide clinician in identifying presumptive PTB for further bacteriologic confirmation CXR can be done in parallel or sequential to DSSM The correct answer is: Bilateral apical infiltrates on CXR is considered specific for active TB

Answer 31

M. TUBERCULOSIS Rod-shaped, non-spore-forming, thin aerobic bacterium Often neutral on Gram’s staining Once stained, the bacilli cannot be decolorized by acid alcohol à this characteristic justifies their classification as acid-fast bacilli Acid fastness: due mainly to the organisms’ high content of mycolic acids, long-chain cross-linked fatty acids, and other cell-wall lipids. In the mycobacterial cell wall, lipids (e.g., mycolic acids) are linked to underlying arabinogalactan and peptidoglycan • This structure results in very low permeability of the cell wall, thus reducing the effectiveness of most antibiotics The correct answer is: Rod-shaped, non-spore-forming, thin aerobic bacterium

Answer 32

The correct answer is: Patient previously treated for TB, declared cured, and is now diagnosed with a new episode of TB

Answer 33

PLEURAL EFFUSION IN TB Straw-colored (sometimes hemorrhagic) Exudative with: • Protein concentration >50% of that in serum (usually ~4–6 g/dL) • Normal to low glucose concentration • pH of ~7.3 (occasionally <7.2) • Detectable white blood cells (usually 500–6000/ μL) Neutrophils may predominate in the early stage Lymphocyte predominance is the typical finding later AFBs are rarely seen on direct smear Cultures often may be falsely negative for M. tuberculosis Positive cultures are more common among postprimary cases Pleural concentration of adenosine deaminase: • May be a useful screening test • TB may be excluded if the value is very low The correct answer is: Normal to low glucose concentration

Answer 34

The correct answer is: Two consecutive specimens collected 1 hour apart should be obtained

Answer 35

The correct answer is: Request for Xpert MTB/Rif

Answer 36

The correct answer is: Inhibits mycolic acid synthesis

Answer 37

DRUG INDUCED HEPATOTOXICITY Routine liver function monitoring NOT needed among asymptomatic patients Serum ALT (SGPT) should only be requested for: (1) individuals who exhibit symptoms of hepatotoxicity such as jaundice, anorexia, nausea, vomiting, or abdominal pain (2) monitoring of patients with baseline risk factors for hepatotoxicity or abnormal baseline LFTs (2-4 weeks after the start of anti-TB medications) All medications should be stopped immediately and evaluated when serum ALT is: • >3x ULN in the presence of symptoms, or • >5x ULN in the absence of symptoms After ALT becomes <2x ULN with symptom resolution, step-wise reintroduction of potentially hepatotoxic anti-TB drugs may be started with Rifampicin (with or without Ethambutol), followed by INH after 3 to 7 days, subsequently rechecking transaminases. Pyrazinamide should be permanently discontinued in patients with prolonged or severe hepatotoxicity The correct answer is: When ALT becomes <2x ULN, step-wise reintroduction may be started with Isoniazid, followed by Rifampicin

Answer 38

The correct answer is: 2 HRZES/1 HRZE/5 HRE

Answer 39

The correct answer is: 2 HRZE / 10 HR

Answer 40

The correct answer is: Proceed to continuation phase and repeat DSSM at the 3rd month

Answer 41

INDICATIONS FOR DST • Retreatment cases • Treatment failure • Contacts of known drug-resistant TB cases *DST should not be routinely performed among new cases of PTB The correct answer is: Send for Xpert MTB/Rif

Answer 42

Minor adverse reactions can be managed with symptomatic therapy. First-line drugs should not be stopped without adequate justification. For major adverse reactions, all drugs must be discontinued. Switching to single drug formulations may be needed. Referral to a specialist is warranted The correct answer is: Manage reactions with symptomatic therapy

Answer 43

LYMPH NODE TB (TUBERCULOUS LYMPHADENITIS) Most common presentation of extrapulmonary TB in both HIV-seronegative individuals and HIV-infected patients Presents as painless swelling of the lymph nodes, most commonly at posterior cervical and supra- clavicular sites (a condition historically referred to as scrofula). Associated pulmonary disease is present in <50% of cases Systemic symptoms are uncommon except in HIV- infected patients The diagnosis is established by fine-needle aspiration biopsy (with a yield of up to 80%) or surgical excision biopsy The correct answer is: Lymphadenitis

Answer 44

TUBERCULIN REACTION SIZE Positive reactions area of induration ≥5 mm in diameter: • Persons with HIV infection • Recent close contacts of infectious cases • Organ transplant recipients • Previously untreated persons whose chest radiograph shows fibrotic lesions consistent with old TB • Persons receiving drugs that suppress the immune system 10-mm cutoff is used to define positive reactions in most other at-risk persons. •Positive reactions area of induration ≥5 mm in diameter: •Persons with HIV infection •Recent close contacts of infectious cases •Organ transplant recipients •Previously untreated persons whose chest radiograph shows fibrotic lesions consistent with old TB •Persons receiving drugs that suppress the immune system •10-mm cutoff is used to define positive reactions in most other at-risk persons. The correct answer is: More than or equal to 5 mm

Answer 45

TB EMPYEMA Less common complication of pulmonary TB Result of the rupture of a cavity, with spillage of a large number of organisms into the pleural space May create a bronchopleural fistula with evident air in the pleural space CXR shows hydropneumothorax with an air-fluid level Pleural fluid: • Purulent and thick and contains large numbers of lymphocytes • Acid-fast smears and mycobacterial cultures are often positive Surgical drainage is usually required as an adjunct to chemotherapy The correct answer is: Result of the rupture of a cavity, with spillage into the pleural space

Answer 46

GENITOURINARY TB Local symptoms predominate Up to 75% of patients have abnormalities on CXR suggesting previous or concomitant pulmonary disease. Urinalysis: • Abnormal results in 90% of cases, revealing pyuria and hematuria • Documentation of culture-negative pyuria in acidic urine should raise the suspicion of TB Culture of three morning urine specimens yields a definitive diagnosis in nearly 90% of cases. Genital TB preferentially affects the epididymis, producing a slightly tender mass that may drain externally through a fistulous tract Responds well to chemotherapy The correct answer is: Culture-negative pyuria in acidic urine should raise the suspicion of TB

Answer 47

SKELETAL TB In bone and joint disease, pathogenesis is related to reactivation of hematogenous foci or to spread from adjacent paravertebral lymph nodes Weight-bearing joints are most commonly affected: • Spine in 40% of cases • Hips in 13% • Knees in 10% Upper thoracic spine is the most common site of spinal TB in children Lower thoracic and upper lumbar vertebrae are usually affected in adults Skeletal TB responds to chemotherapy Severe cases may require surgery The correct answer is: Spine

Answer 48

TB PERICARDITIS Due either to direct extension from adjacent mediastinal or hilar lymph nodes or to hematogenous spread, pericardial TB has often been a disease of the elderly in countries with low TB prevalence. The onset may be subacute, although an acute presentation, with dyspnea, fever, dull retrosternal pain, and a pericardial friction rub, is possible. The effusion is exudative in nature, with a high count of lymphocytes and monocytes. Hemorrhagic effusion is common. Direct smear examination is very rarely positive. Without treatment, pericardial TB is usually fatal The correct answer is: High count of lymphocytes and monocytes are documented in fluid

Answer 49

The correct answer is: TB pericarditis

Answer 50

The correct answer is: Resistance to at least both Isoniazid and Rifampicin

Answer 51

The correct answer is: For patients with TB meningitis, antiretroviral therapy should be initiated before the intensive phase of TB treatment.

Answer 52

The correct answer is: Blood pressure of 100/60 with a heart rate of 110 bpm

Answer 53

SALMONELLA TYPHI Incubation period averages 10–14 days but ranges from 5 to 21 days, depending on the inoculum size and the host’s health and immune status Most prominent symptom = prolonged fever (38.8°–40.5°C; 101.8°– 104.9°F), which can continue for up to 4 weeks if untreated. Early physical findings of enteric fever include: • Rash (“rose spots”; 30%): make up a faint, salmon-colored, blanching, maculopapular rash located primarily on the trunk and chest • Hepatosplenomegaly (3–6%) • Epistaxis • Relative bradycardia at the peak of high fever (<50%) The correct answer is: Prolonged fever

Answer 54

PATHOPHYSIOLOGY OF TYPHOID All Salmonella infections begin with ingestion of organisms, most commonly in contaminated food or water Infectious dose ranges from 200 colony-forming units (CFU) to 106 CFU Ingested dose is an important determinant of incubation period and disease severity The following increase susceptibility to Salmonella infection: • Conditions that decrease either stomach acidity (an age of <1 year, acid suppression therapy, or achlorhydric disease) • Conditions that decrease intestinal integrity (inflammatory bowel disease, cytotoxic chemotherapy, prior gastrointestinal surgery, or alteration of the intestinal microbiome by antibiotic administration) The correct answer is: Increase stomach acidity

Answer 55

SALMONELLA Gram-negative, non-spore-forming, facultatively anaerobic bacilli The initial identification of salmonellae in the clinical microbiology laboratory is based on growth characteristics: • Produce acid on glucose fermentation • Reduce nitrates • Do not produce cytochrome oxidase All salmonellae except Salmonella Gallinarum-Pullorum are motile by means of peritrichous flagella, and all but S. Typhi produce gas (H2S) on sugar fermentation The correct answer is: Produces acid on glucose fermentation

Answer 56

The correct answer is: Antibody detection

Answer 57

The correct answer is: Ceftriaxone 2-3 g IV Q24 hours x 14 days

Answer 58

The correct answer is: Ampicillin

Answer 59

``` GASTROINTESTINAL COMPLICATIONS Gastrointestinal bleeding (10–20%) and intestinal perforation (1–3%) most commonly occur in the third and fourth weeks of illness ``` Result from hyperplasia, ulceration, and necrosis of the ileocecal Peyer’s patches at the initial site of Salmonella infiltration The correct answer is: Third to fourth week of illness

Answer 60

ANTIBIOTIC THERAPY OF TYPHOID Prompt administration of appropriate antibiotic therapy prevents severe complications of enteric fever and results in a case–fatality rate of <1% The initial choice of antibiotics depends on the susceptibility of the S. Typhi and S. Paratyphi strains in the area of residence or travel For treatment of drug-susceptible typhoid fever: • Fluoroquinolones are the most effective class of agents • Cure rates of ~98% and relapse and fecal carriage rates of <2% • Experience is most extensive with ciprofloxacin The correct answer is: Fluoroquinolones

Answer 61

MANAGEMENT OF CHRONIC CARRIERS Can be treated for 4–6 weeks with an appropriate oral antibiotic Treatment with oral amoxicillin, TMP-SMX, ciprofloxacin, or norfloxacin is ~80% effective in eradicating chronic carriage of susceptible organisms. In cases of anatomic abnormality (e.g., biliary or kidney stones), eradication often requires both antibiotic therapy and surgical correction. The correct answer is: Refer to Surgery for surgical management

Answer 62

The correct answer is: Pregnant patient who is still febrile after 3-5 days of therapy with a first line agent

Answer 63

The correct answer is: Ingestion of contaminated water

Answer 64

HPIM 20th Ed, Page 1290 MANIFESTATIONS OF LEPTOSPIROSIS Mild form: nonspecific symptoms such as fever, headache, and myalgia Severe leptospirosis: jaundice, renal dysfunction, and hemorrhagic diathesis (often referred to as Weil’s syndrome) With or without jaundice, severe pulmonary hemorrhage is increasingly recognized as an important presentation of severe disease Triad Weil’s syndrome • Hemorrhage • Jaundice • Acute kidney injury The correct answer is: Meningitis

Answer 65

PATHOGENESIS OF LEPTOSPIROSIS Transmission occurs through cuts, abraded skin, or mucous mem- branes, especially the conjunctival and oral mucosa After entry, the organisms proliferate, cross tissue barriers, and disseminate hematogenously to all organs (leptospiremic phase) • During this initial incubation period, leptospires can be isolated from the bloodstream During the immune phase, the appearance of antibodies coincides with the disappearance of leptospires from the blood However, the bacteria persist in various organs, including liver, lung, kidney, heart, and brain. The correct answer is: During the initial incubation period, leptospires cannot be isolated from the bloodstream

Answer 66

HPIM 20th Ed, Page 1290 BIPHASIC COURSE OF LEPTOSPIROSIS Acute leptospiremic phase: • Characterized by fever of 3–10 days’ duration • Organism can be cultured from blood and detected by PCR Immune phase • Resolution of symptoms may coincide with the appearance of antibodies • Leptospires can be cultured from the urine The correct answer is: Leptospiremic phase

Answer 67

The correct answer is: Fever

Answer 68

COURSE OF LEPTOSPIROSIS Majority of cases are thought to be relatively mild, presenting as the sudden onset of a febrile illness. Most patients are asymptomatic or only mildly ill and do not seek medical attention. The natural course of mild leptospirosis usually involves spontaneous resolution within 7–10 days, Severe disease is often rapidly progressive Acute kidney injury is common in severe disease: • Presents after several days of illness • Can be either nonoliguric or oliguric • Typical electrolyte abnormalities include hypokalemia and hyponatremia The correct answer is: Majority of cases are thought to be severe, presenting as the Weil’s syndrome

Answer 69

HIGH RISK FEATURES OF LEPTOSPIROSIS Clinical features associated with increased risk for mortality include: • Altered mental status • Respiratory insufficiency (rales, infiltrates) • Hemoptysis • Oliguric hyperkalemic acute renal failure • Cardiac involvement (myocarditis, complete or incomplete heart block, AF) The correct answer is: Hemoptysis

Answer 70

The correct answer is: Polymerase chain reaction

Answer 71

A definitive diagnosis of leptospirosis is based on: • isolation of the organism from the patient • on a positive result in the polymerase chain reaction (PCR) • or on seroconversion or a rise in antibody titer. Preferably, a fourfold or greater rise in titer is detected between acute- and convalescent-phase serum specimens. The correct answer is: Culture and isolation

Answer 72

The correct answer is: Serum potassium of 4.8 mmol/L

Answer 73

The correct answer is: Penicillin-G

Answer 74

The correct answer is: Doxycycline 200 mg once daily for 3-5 days to be started within 24 to 72 hours from exposure

Answer 75

The correct answer is: Azithromycin 250mg tab, 1 dose

Answer 76

The correct answer is: 30 year old male with hemoptysis and ARDS

Answer 77

The correct answer is: Schistosoma haematobium

Answer 78

The correct answer is: Schistosoma japonicum

Answer 79

PATHOPHYSIOLOGY OF SCHISTOSOMIASIS Contracted through contact with freshwater bodies harboring infected intermediate-host snails Cercariae • Infective larval stage released from the snail • Penetrates intact human skin within a few minutes after attaching to the skin. After penetration, the cercariae transform to schistosomula, which then enter a small vein or lymphatic vessel, circulate in the bloodstream through the lung capillaries, and are pumped via the heart to all parts of the body to reach the portal vein There, the worms mature into adult males or females, pair, and migrate to their final location in the mesenteric or pelvic venous plexus. The correct answer is: Penetration of cercariae into intact skin

Answer 80

The schistosome egg is the only stage of the parasites’ life cycle that can be detected in humans, either in excreta or in tissue biopsies The eggs are large and can easily be distinguished morpho- logically from other helminth eggs. The correct answer is: Schistosome egg

Answer 81

Cercarial Dermatitis (“Swimmer’s Itch”) • Cercarial penetration of the skin may result in a maculopapular rash called cercarial dermatitis or “swimmer’s itch Acute Schistosomiasis (Katayama Fever) • Symptomatic acute schistosomiasis • Usually seen in travelers who have contracted the infection for the first time • Onset occurs between 2 weeks and 3 months after exposure to the parasite • Symptoms may appear suddenly and include fever, myalgia, general malaise and fatigue, headache, nonproductive cough, and intestinal symptoms such as abdominal tenderness or pain Many patients recover spontaneously from acute schistosomiasis after 2–10 weeks Katayama fever is rare in people chronically exposed to infection in areas endemic for S. mansoni or S. haematobium. The correct answer is: It is rare in people chronically exposed to the infection

Answer 82

The correct answer is: Praziquantel

Answer 83

HEPATOSPLENIC SCHISTOSOMIASIS Caused by schistosome eggs trapped in liver tissue Occurs in S. mansoni and S. japonicum infections Early inflammatory hepatosplenic schistosomiasis is the main entity seen in children and adolescents. Late hepatosplenic schistosomiasis with periportal or Symmers fibrosis: • May develop in young and middle-aged adults with long- standing, high-level exposure to infection. • Ascites, attributable both to portal hypertension and to hypoalbuminemia, may be seen, especially in S. japonicum infection. Patients with severe hepatosplenic disease and portal hypertension may develop esophageal varices detectable by endoscopy or ultrasound • Experience repeated bouts of hematemesis, melena, or both • Hematemesis is the most severe complication of hepatosplenic schistosomiasis, and death may result from massive loss of blood The correct answer is: Patients with severe hepatosplenic disease and portal hypertension may develop esophageal varices

Answer 84

The correct answer is: Schistosoma hematobium

Answer 85

S. haematobium has been classified by the International Agency for Research on Cancer (IARC) as definitely carcinogenic to humans (i.e., a group 1 carcinogen) • Chronic S. haematobium infection is associated with squamous cell carcinoma of the urinary bladder The signs and symptoms of S. haematobium infection relate to the worms’ predilection for the veins of the urogenital tract. A characteristic sign in the active stage is painless, terminal hematuria As the infection progresses, the inflammatory component decreases and fibrosis becomes more prominent. Cystoscopy reveals “sandy patches” composed of large numbers of calcified eggs surrounded by fibrous tissue and an atrophic mucosal surface. The correct answer is: Painless, terminal hematuria

Answer 86

TETANUS Diagnosed on clinical grounds The CDC defines probable tetanus as “an acute illness with muscle spasms or hypertonia in the absence of a more likely diagnosis.” C. tetani • Anaerobic, gram-positive, spore-forming rod • Spores are highly resilient and can survive readily in the environment throughout the world • Spores resist boiling and many disinfectants Superficial abrasions to the limbs are the most common infection sites in adults Deeper infections (e.g., attributable to open fracture, abortion, or drug injection) are associated with more severe disease and worse outcomes Tetanus is a rare disease in the developed world. The correct answer is: Tetanus is diagnosed on clinical grounds

Answer 87

DIAGNOSIS OF TETANUS Treatment should not be delayed while laboratory tests are conducted Culture of C. tetani from a wound provides supportive evidence Serum anti-tetanus immunoglobulin G also may be measured in a sample taken before the administration of antitoxin or immunoglobulin Polymerase chain reaction also has been used for detection of tetanus toxin, but its sensitivity is unknown The correct answer is: Culture of C. tetani from a wound provides supportive evidence

Answer 88

The most common initial symptoms are trismus (lockjaw), muscle pain and stiffness, back pain, and difficulty swallowing. The diagnosis of tetanus is based on clinical findings Metronidazole (400 mg rectally or 500 mg IV every 6 h for 7 days) is preferred for antibiotic therapy An alternative is penicillin (100,000–200,000 IU/kg per day), although this drug theoretically may exacerbate spasms and in one study was associated with increased mortality. The correct answer is: Metronidazole

Answer 89

MANAGEMENT OF TETANUS Identify the entry wound, clean and debride any necrotic material. Metronidazole (400 mg rectally or 500 mg IV every 6 h for 7 days) is the preferred antibiotic. • Penicillin is an alternative but may exacerbate spasms Use sedatives or magnesium IV, and cardiovascularly inert, non-depolarizing neuromuscular blockers. Secure airway early and do tracheostomy for patients with severe tetanus Administer 3000-5000 IU of human tetanus IG (TIG) IM and around the wound. • Human TIG is the preparation of choice Give full primary course of immunization (tetanus toxin is poorly immunogenic and the immune response following natural infection is inadequate) Equine-derived antitoxin is available widely and is used in low-income countries at a dosage of 10,000–20,000 U administered IM as a single dose or as divided doses after testing for hypersensitivity. The correct answer is: Tetanus immune globulin

Answer 90

PREVENTION OF MATERNAL AND NEONATAL TETANUS WHO recommendation: two doses of tetanus toxoid at least 4 weeks apart to previously unimmunized pregnant women In high-risk areas, a more intensive approach has been successful: • all women of childbearing age receiving a primary course along with education on safe delivery and postnatal practices The correct answer is: 2 doses of tetanus toxoid at least 4 weeks apart

Answer 91

Rapid development of tetanus is associated with more severe disease and poorer outcome; it is important to note time of onset and length of incubation period. The correct answer is: Incubation period of 5 days

Answer 92

PATHOPHYSIOLOGY OF RABIES Rapidly progressive, acute infectious disease of the central nervous system (CNS) in humans and animals that is caused by infection with rabies virus. Rabies has encephalitic and paralytic forms that progress to death. Rabies is a zoonotic infection that occurs in a variety of mammals throughout the world Incubation period of rabies (defined as the interval between expo- sure and the onset of clinical disease) is usually 20–90 days Rabies virus spreads centripetally along peripheral nerves toward the spinal cord or brainstem via retrograde fast axonal transport Rabies virus replicates in acinar cells of the salivary glands and is secreted in the saliva of rabid animals that serve as vectors of the disease There is no well-documented evidence for hematogenous spread of rabies virus. The correct answer is: Rabies is a zoonotic infection

Answer 93

PATHOLOGY OF RABIES Mild inflammatory changes in the CNS in rabies, with mononuclear inflammatory infiltration in the leptomeninges, perivascular regions, and parenchyma, including microglial nodules called Babes nodules Negri bodies are eosinophilic cytoplasmic inclusions in brain neurons that are composed of rabies virus proteins and viral RNA. The correct answer is: Negri bodies

Answer 94

Two acute neurologic forms of rabies are seen in humans: the encephalitic (furious) form in 80% and the para- lytic form in 20%. Encephalitic Rabies • Episodes of hyperexcitability are typically followed by periods of complete lucidity that become shorter as the disease progresses • Rabies encephalitis is distinguished by early brainstem involvement, which results in the classic features of hydrophobia (involuntary, painful contraction of the diaphragm and accessory respiratory, laryngeal, and pharyngeal muscles in response to swallowing liquids) and aerophobia (the same features caused by stimulation from a draft of air) Paralytic rabies (20%) • Muscle weakness predominates • Cardinal features of encephalitic rabies (hyperexcitability, hydrophobia, and aerophobia) are lacking The correct answer is: Brainstem dysfunction progresses rapidly and coma is the rule

Answer 95

MANAGEMENT OF RABIES There is no established treatment for rabies. Since there is no effective therapy for rabies, it is extremely important to prevent the disease after an animal exposure (i.e. postexposure prophylaxis) Healthy dogs, cats, or ferrets may be confined and observed for 10 days PEP is not necessary if the animal remains healthy If the animal develops signs of rabies during the observation period, it should be euthanized immediately; the head should be transported to the laboratory under refrigeration, rabies virus should be sought by DFA testing, and viral isolation should be attempted by cell culture and/or mouse inoculation. The correct answer is: There is no effective therapy for rabies

Answer 96

DIAGNOSIS OF RABIES Diagnosis should be considered in patients presenting with acute atypical encephalitis or acute flaccid paralysis, including those in whom Guillain-Barré syndrome is suspected Lack of hydrophobia is not unusual in rabies Once rabies is suspected, rabies-specific lab- oratory tests should be performed to confirm the diagnosis ``` Diagnostically useful specimens include: • Serum • CSF • Fresh saliva • Skin biopsy samples from the neck, and brain tissue (rarely obtained before death) ``` Negative antemortem rabies-specific laboratory tests never exclude a diagnosis of rabies, and tests may need to be repeated after an interval for diagnostic confirmation. The correct answer is: Negative antemortem rabies-specific laboratory tests usually exclude a diagnosis of rabies

Answer 97

All previously unvaccinated persons should be passively immunized with rabies immune globulin (RIG). • If RIG is not immediately available, it should be administered no later than 7 days after the first vaccine dose. • After day 7, endogenous antibodies are being produced, and passive immunization may actually be counterproductive. If anatomically feasible, the entire dose of RIG (20 IU/kg) should be infiltrated at the site of the bite; otherwise, any RIG remaining after infiltration of the bite site should be administered IM at a distant site Four 1-mL doses of rabies vaccine should be given IM in the deltoid area. (The anterolateral aspect of the thigh also is acceptable in children.) • Gluteal injections, which may not always reach muscle, should not be given and have been associated with rare vaccine failures. Ideally, the first dose should be given as soon as possible after exposure; failing that, it should be given without further delay. The three additional doses should be given on days 3, 7, and 14; a fifth dose on day 28 is no longer recommended. Pregnancy is not a contraindication for immunization. The correct answer is: Rabies IG 20 IU/kg at the site of the bite + Rabies vaccine on Day 0, 3, 7, 14.

Answer 98

The correct answer is: Category I Exposure

Answer 99

The correct answer is: RIG should be started immediately

Answer 100

The correct answer is: Suture the wound as soon as possible to avoid rabies infection

Answer 101

The correct answer is: A 30 year old female with an open wound licked by a stray cat

Answer 102

A. Earliest manifestation is leukopenia – starts in the febrile phase and progressively decreases during the critical phase together with thrombocytopenia and hemoconcentration B. Typically lasts for 7 days- typically lasts for 24-48 hrs C. Rapid decline in platelet count precedes plasma leakage D. Coincides with the reabsorption of extravascular fluid and increased risk of acute pulmonary edema- corresponds to recovery phase Febrile Phase • High-grade fever • Lasts 2-7 days • Facial flushing, skin erythema, generalized body ache, myalgia, arthralgia, retro-orbital eye pain, photophobia, rubeliform exanthema and headache • Sore throat, injected pharynx, and conjunctival injection • Anorexia, nausea and vomiting • Earliest abnormality in CBC is decreasing WBC count • Positive tourniquet test suggestive of Dengue • Mild hemorrhagic manifestations (bleeding gums/nose, prolonged heavy menses) Critical Phase • Defervescence • Onset of warning signs with capillary permeability • Increasing hematocrit (hemoconcentration) due to plasma leakage o Ascites and pleural effusion may occur after rigorous IV fluid therapy • Rapidly declining platelet count • Shock due to critical volume of plasma lost through leakage Recovery Phase • Gradual reabsorption of extravascular compartment fluid takes place in the following 48−72 hours • General well- being improves, appetite returns, gastrointestinal symptoms abate, haemodynamic status stabilizes, and diuresis ensues. • “isles of white in the sea of red” • CBC picture o Hematocrit stabilizes or may be lower due to reabsorbed fluid o Rise in WBC to normal o Platelet count normalizes albeit much later than normalization of WBC The correct answer is: Rapid decline in platelet count precedes plasma leakage

Answer 103

The correct answer is: Peak of fever coincides with peak of viremia

Answer 104

The correct answer is: Dengue with warning signs

Answer 105

The correct answer is: Admit to hospital regular room and administer Paracetamol for fever with advise to increase oral fluid intake as tolerated

Answer 106

LABORATORY DIAGNOSIS OF DENGUE A diagnosis of dengue infection is confirmed by the detection of the virus, the viral genome or NS1 Ag, or seroconversion of IgM or IgG (from negative to positive IgM/IgG or four-fold increase in the specific antibody titre) in paired sera (see Table 5). A positive IgM serology or a haemagglutinin inhibition test (HIA) antibody titre of 1280 or higher (or comparable figures by ELISA in a single specimen), are all diagnostic criteria of a probable dengue infection. Both probable and confirmed dengue cases should be notified to health authorities (1–4, 9, 30). Antigen detection tests such as Dengue NS1 are best done during Days 1-5 of fever to confirm acute dengue infection Serologic tests are done after day 5 of fever and during the critical and convalescent phase to detect recent Dengue infection. Paired sera taken from acute phase (Days 1-5) and from days 15-21 with evidence of serologic conversion can also be used to confirm dengue infection, albeit, with very long waiting time (until the convalescent phase) The correct answer is: Start IV therapy with lactated ringer’s solution at 10ml/kg/hr then decrease to 5-7ml/kg/hr once hematocrit normalizes or decreases

Answer 107

The correct answer is: Start IV therapy with 0.9 NaCl at 20ml/kg/hr for 30 minutes then reassess BP and hematocrit

Answer 108

The correct answer is: Check if there’s overt bleeding and maintain IV at 20ml/kg/hr.

Answer 109

The correct answer is: Obtain tracheal aspirate for culture and sensitivity and start Vancomycin at 15mg/kg IV q8 + Piperacillin-Tazobactam at 4.5g IV q6 + Levofloxacin 750mg IV q24

Answer 110

The correct answer is: Seven or more days of hospitalization prior to occurrence of VAP

Answer 111

The correct answer is: Ertapenem

Answer 112

A. Apply insect repellant everytime they would go on tours during the day- Anopheles bites from dusk to dawn B. Start Mefloquine 250mg PO once a week, 2 weeks before their departure to be continued for 4 weeks after their arrival here in the Philippines- not recommended for those with psychiatric disorders C. Start Doxycycline 100mg PO daily 2 days before their departure to be continued for 4 weeks after their arrival here in the Philippines D. Start Hydoxychloroquine 200mg 2 days before their departure be continued for 4 weeks after their arrival here in the Philippines- dose and timing is not correct; not advisable in areas where there is chloroquine-resistant P. falciparum The correct answer is: Start Doxycycline 100mg PO daily 2 days before their departure to be continued for 4 weeks after their arrival here in the Philippines

Answer 113

The correct answer is: Plasmodium malariae

Answer 114

The correct answer is: Plasmodium falciparum

Answer 115

Patient has relapse of malaria and it is usually caused by P. vivax or P. ovale but the smear showed ring form trophozoites and schuffner’s dots and no signs of oval or enlarged RBCs --> P.vivax A. Cause of the malignant tertian fever- P. vivax causes benign tertian fever whereas falciparum causes malignant (severe) tertian fever B. Capable of producing hypnozoites that remain dormant in the liver- dormant parasite can live for 2 weeks up to a year in the liver C. Prefers older RBCs – prefers young RBCs and reticulocytes D. Infected erythrocytes are enlarged and oval in shape with characteristic schuffner’s dots- characteristic of P.ovale The correct answer is: Capable of producing hypnozoites that remain dormant in the liver

Answer 116

The correct answer is: Primaquine for 14 days

Answer 117

A. Stable transmission usually occurs in hypoendemic areas- stable transmission occurs in hyper and holoendemic areas; unstable transmission occurs in hypoendemic areas B. Anopheles mosquito must survive for more than 7 days for it to be able to transmit sporozoites- Mosquito longevity is an important determinant of transmission; sporogony lasts for 7-8 days therefore a mosquito must stay alive for more than 7 days to transmit the sporozoites C. Lower temperatures are more favorable for sporogony and therefore transmission- Sporogony (sporozoite development) is not completed in cooler temperatures such as < 21C with P.falciparum and < 16% with P. vivax D. Transmission is usually high in high altitude areas- high altitudes have cooler temperatures and therefore not favorable for sporogony The correct answer is: Anopheles mosquito must survive for more than 7 days for it to be able to transmit sporozoites

Answer 118

A.Infected erythrocytes form rosettes and have reduced deformability compromising their passage through capillaries and venules Rosette formation, agglutination, cytoadherence are central to the pathogenesis of falciparum malaria B. Characteristic paroxysm of fever, chills and rigors corresponding to rupture of schizonts and release of pro-inflammatory cytokines occurs every 72 hours P. Falciparum exhibits tertian periodicity (every 48 hrs) C. P. falciparum infects younger RBC’s and reticulocytes Infects RBCs of all ages D. Infection with P.falciparum, due to its severity, can result to lifelong immunity against this parasite. The complexity of the immune response in malaria, the sophistication of the parasites’ evasion mechanisms, and the lack of a good in vitro correlate with clinical immunity have all slowed progress toward an effective vaccine. The correct answer is: Infected erythrocytes form rosettes and have reduced deformability compromising their passage through capillaries and venules

Answer 119

The correct answer is: Anemia

Answer 120

The correct answer is: Presence of more mature forms of P. falciparum in the blood smear

Answer 121

The correct answer is: Salmonella

Answer 122

The correct answer is: It is unique among all viral pneumonias in that it lacks upper respiratory symptoms

Answer 123

The correct answer is: 43/M with TB bronchiectasis

Answer 124

A. Belongs to Influenza group A with hemagglutinin subtype 1 and neuraminidase subtype 1 B. Enveloped virus with segmented single-stranded, negative-sense RNA that allows gene reassortment C. Spread is through small- and large-droplets from coughing or sneezing D. Underwent antigenic drift enabling it to cause a pandemic- antigenic shift causes pandemics The correct answer is: Underwent antigenic drift enabling it to cause a pandemic

Answer 125

The correct answer is: Measles Virus

Answer 126

The correct answer is: Rubeola

Answer 127

The correct answer is: Varicella zoster virus

Answer 128

The correct answer is: 55/M with TB bronchiectasis presenting with 2 day history of increased sputum production, dyspnea, fever of 38C, BP 100/70, HR 120, RR 26, O2 saturation of 90% on room air

Answer 129

The correct answer is: RR ≥ 20

Answer 130

The correct answer is: Pulmonary Infection

Answer 131

The correct answer is: Most common pathogen associate molecular pattern (PAMP) that initiates the inflammatory response is the lipid A moiety of the LPS

Answer 132

The correct answer is: Get baseline serum lactate levels

Answer 133

The correct answer is: Start Cetfriaxone 2g IV + Azithromycin 500mg/tab PO OD

Answer 134

The correct answer is: Do Passive Leg Raising

Answer 135

The correct answer is: Blood cultures are positive in 50% of the time among septic patients

Answer 136

The correct answer is: Insulin must be initiated following two consecutive capillary blood glucose readings of more than 180mg/dL

Answer 137

A. 25/F with recurrent acute suppurative tonsillopharyngitis –only for patients < 6 years old B. 28/M with aphthous ulcers lasting for 2 weeks- must be more than 1 month duration C. 5/F with invasive cervical cancer- only for patients > 6 years old D. 30/M with primary adrenal insufficiency from TB adrenalitis The correct answer is: 30/M with primary adrenal insufficiency from TB adrenalitis

Answer 138

The correct answer is: 28/F with negative HIV ELISA test after 3 months of initial diagnosis of HIV

Answer 139

The correct answer is: Sharing of sex toys

Answer 140

The correct answer is: Herpes Simplex ulcer

Answer 141

The correct answer is: Hep B Ig

Answer 142

The correct is: He can start post-exposure prophylaxis with antiretroviral drugs

Answer 143

The correct answer is: Repeat the test

Answer 144

The correct answer is: Syncytia formation

Answer 145

The correct answer is: Re-test after 3-6 months

Answer 146

The correct answer is: 10 years

Answer 147

The correct answer is: 10 years

Answer 148

A. Most common CV disease is HIV-associated cardiomyopthy- coronary artery disease B. Anemia is the most common hematologic abnormality and is commonly caused by Tenofovir – Zidovudine blocks maturation of RBC --> most common finding is increased MCV C. Proteinuria is the hallmark of HIV-associated nephropathy (HIVAN)- edema and hypertension is rare. HIVAN typically occurs at CD4+ T cell count of less than 200 D. Most common thyroid abnormality is subclinical hyperthyroidism- subclinical hypothyroidism The correct answer is: Proteinuria is the hallmark of HIV-associated nephropathy (HIVAN)

Answer 149

The correct answer is: Zidovudine

Answer 150

The correct answer is: Common in patients with underlying, untreated tuberculosis

Answer 151

The correct answer is: Yersinia enterocolitica produces cytotoxin responsible for fever and abdominal pain

Answer 152

The correct answer is: Staphyloccous aureus

Answer 153

The correct answer is: Vibrio cholerae

Answer 154

A. Obtain fecalysis – work-up is needed if patient presents with fever T>38.5C, bloody diarrhea, severe symptoms, more than 4 hrs duration and with recent antibiotic use B. Advised to increase fluid intake – fluid and electrolyte replacement are cornerstone in the management of acute diarrhea C. Start Ciprofloxacin 500mg PO q12 for 5 days- febrile dysentery can be empirically treated with Ciprofloxacin D. Start loperamide- avoided in febrile dysentery since it can prolong or exacerbate the symptoms The correct answer is: Start loperamide

Answer 155

The correct answer is: Shigella dysenteriae

Answer 156

The correct answer is: Reactive arthritis occuring after Shigellosis

Answer 157

The correct answer is: Asymptomatic cyst passage

Answer 158

The correct answer is: Uncertain diagnosis 1 week of inpatient evaluation

Answer 159

The correct answer is: Lymphoma

Answer 160

The correct answer is: Tuberculosis

Answer 161

A. Chest xray has relatively low sensitivity hence, it is not advisable to include this as part of the extensive work-up of FUO- simple and low-cost and remains obligatory in all patients B. Abdominal CT is preferred over Abdominal sonography- ultrasound is preferable in the initial obligatory work-up C. Multiple blood cultures and at least one urine culture must be done on all patients- Performing more than three blood cultures or more than one urine culture is useless in patients with FUO in the absence of PDCs (e.g., a high level of clinical suspicion of endocarditis). D. Antibiotic and glucocorticoids must be stopped prior to doing diagnostic tests The correct answer is: Antibiotic and glucocorticoids must be stopped prior to doing diagnostic tests

Answer 162

A. CBC with platelet count and differential count B. Chest Xray PA upright C. ESR and CRP D. TSH – not included in the initial obligatory test for FUO; only symptom that can be attributed to thyroid dysfunction is weight loss- no tremors, palpitations, diarrhea typical of hyperthyroidism The correct answer is: TSH

Answer 163

A. Start HRZE B. Get sputum AFB x 2 – sputum samples in miliary TB are oftentimes negative C. Get bronchoalveolar lavage specimen- need to test resistance to TB meds D. Perform Tuberculin Skin Test (TST)- usually negative in miliary TB The correct answer is: Get bronchoalveolar lavage specimen

Answer 164

The correct answer is: Treat the partner only after appropriate tests are done

Answer 165

The correct answer is: Start Metronidazole 500mg BID PO for 7 days

Answer 166

The correct answer is: Microscopic examination is less sensitive than culture therefore culture is needed prior to therapy

Answer 167

A. Therapy should be withheld after appropriate specimen is collected for microscopy- presumptive therapy must be initiated based on the patient’s risk profile even in the absence of diagnostic tests B. Negative RPR rules out the diagnosis of Primary Syphilis and repeat testing is not warranted for this patient- 30% of syphilitic chancre is associated with negative serologic test C. Likely etiologic agent for this case is HSV-2- see table 131-7. based on the clinical features and characteristic of the ulcer, the likely agent is still T. pallidum D. HIV testing and counseling must be done for all patients with genital ulcer The correct answer is: HIV testing and counseling must be done for all patients with genital ulcer

Answer 168

The correct answer is: Hemophilus ducreyi

Answer 169

The correct answer is: Ceftriaxone 250mg IM single dose

Answer 170

A. Reovirus- tick-borne (Colorado Tick Fever), viral encephalitis B. Retrovirus- HIV C. Filovirus- Ebola virus D. Flavivirus- Dengue, Yellow Fever The correct answer is: Flavivirus

Answer 171

A. Males are more often affected – females are more often affected B. Severity of Dengue drops after the age of 12 C. Malnutrition is a risk factor- malnutrition is protective D. Previous infection with Dengue type 4 with subsequent re-infection with Dengue type 2 Dengue type 1 --> type 2 is more severe The correct answer is: Severity of Dengue drops after the age of 12

Answer 172

A. Males are more often affected – females are more often affected B. Severity of Dengue drops after the age of 12 C. Malnutrition is a risk factor- malnutrition is protective D. Previous infection with Dengue type 4 with subsequent re-infection with Dengue type 2 Dengue type 1 --> type 2 is more severe The correct answer is: Severity of Dengue drops after the age of 12

Answer 173

A.West Nile Virus- Culex mosquito B.Chikungunya C.Yellow Fever D.Dengue The correct answer is: West Nile Virus- Culex mosquito

Answer 174

The correct answer is: Apply OFF Lotion during the day when she’s at work

Answer 175

The correct answer is: Elevated hematocrit

Answer 176

The correct answer is: Yellow Fever

Answer 177

The correct answer is: Hep A and Hep B

Answer 178

The correct answer is: High count of lymphocytes and monocytes are documented in fluid

Answer 179

The correct answer is: Resistance to at least both Isoniazid and Rifampicin

Answer 180

The correct answer is: For patients with TB meningitis, antiretroviral therapy should be initiated before the intensive phase of TB treatment.

Answer 181

The correct answer is: Rifampicin

Answer 182

The correct answer is: 50/M diabetic and smoker

Answer 183

The correct answer is: There is no need to treat latent TB in the general population

Answer 184

The correct answer is: Lymph nodes

Answer 185

The correct answer is: Aedes aegypti

Answer 186

The correct answer is: Dengue with warning signs

Answer 187

The correct answer is: Transfuse packed red blood cells

Answer 188

The correct answer is: Routine fecalysis

Answer 189

The correct answer is: Yersinia enterocolitica

Answer 190

The correct answer is: Ampicillin can be started by the patient on the first symptoms and diarrhea

Answer 191

The correct answer is: A+B+C

Answer 192

The correct answer is: Ceftriaxone 2g IV q24

Answer 193

The correct answer is: Exposure to contaminated soil

Answer 194

The correct answer is: Precaution and proper clothing and foot wear

Answer 195

The correct answer is: Initiate dialysis

Answer 196

The correct answer is: P. falciparum

Answer 197

The correct answer is: Mefloquine

Answer 198

The correct answer is: Urine output of < 0.5cc/kg/hr

Answer 199

The correct answer is: IV fluids of 20ml/kg in the first 3 hours

Answer 200

The correct answer is: 60 mg/kg PO in 3 divided doses for 1 day

Answer 201

The correct answer is: Systolic hypertension

Answer 202

The correct answer is: TIG + Tetanus Toxoid

Answer 203

The correct answer is: RIG and rabies vaccine

Answer 204

The correct answer is: Rabies is a zoonotic infection

Answer 205

The correct answer is: Oral candidiasis

Answer 206

The correct answer is: Needle-sharing during injection drug use

Answer 207

The correct answer is: For patients with TB meningitis, antiretroviral therapy should be initiated before the intensive phase of TB treatment.

Answer 208

The correct answer is: Chest and abdominal CT scan

Answer 209

The correct answer is: Negri bodies

Answer 210

The correct answer is: Brainstem dysfunction progresses rapidly and coma is the rule

Answer 211

The correct answer is: Infected erythrocytes form rosettes and have reduced deformability compromising their passage through capillaries and venules

Answer 212

The correct answer is: Anemia

Answer 213

The correct answer is: Presence of more mature forms of P. falciparum in the blood smear

Answer 214

The correct answer is: Measles Virus

Answer 215

The correct answer is: Varicella zoster virus

Answer 216

The correct answer is: Pulmonary Infection

Answer 217

The correct answer is: Most common pathogen associate molecular pattern (PAMP) that initiates the inflammatory response is the lipid A moiety of the LPS

Answer 218

The correct answer is: Start Cetfriaxone 2g IV + Azithromycin 500mg/tab PO OD

Answer 219

The correct answer is: 30/M with primary adrenal insufficiency from TB adrenalitis

Answer 220

The correct answer is: 28/F with negative HIV ELISA test after 3 months of initial diagnosis of HIV

Answer 221

The correct answer is: Herpes Simplex ulcer

Answer 222

The correct answer is: He can start post-exposure prophylaxis with antiretroviral drugs

Answer 223

The correct answer is: Syncytia formation

Answer 224

The correct answer is: Proteinuria is the hallmark of HIV-associated nephropathy (HIVAN)

Answer 225

The correct answer is: Zidovudine

IDS Flashcards

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