Infectious Disease - Diseases Flashcards

Question

Erlichosis

Answer 1

Caused by parasite Erlichia Chaffeensis; transmitted by Lone Star Tick) Presents with fever, malaise, rash Findings: Monocytes/neutrophils with "berry-like" cytoplasmic inclusions (morulae)

Answer 2

Severe pneumonia caused by gram negative Legionella; usually seen in older patients with risk factors (tobacco, alcohol, DM, chronic illness, etc.) Transmitted by aeresolized droplets from environmental water source (air conditioners); no person-to-person transmission Presents with severe pneumonia, fever, GI and CNS symptoms; milder, flu-like presentation = Pontiac Fever); antibodies can x-react with the enzyme responsible for VWF degradation leading to thrombotic thrombocytopenic purpura, intravascular hemolysis, elevated BUN/Creatinine Dx: Presence of antigen in urine, growth on charcoal yeast extract agar Trx: Macrolide or Fluoroquinolone

Answer 3

Caused by trichomonas vaginalis; responsible for 10% of women seeking STI treatment Presents with vaginitis - vaginal pruritis, dysuria, foul-smelling, green discharge; finding of "strawberry cervix" seen Diagnosed by the presence of mobile, flaggelated trophozoites on discharge wet prep Treatment: Metronidazole for patient and prophylaxis for partner

Answer 4

Caused by gram negative pathogen Vibrio Cholera Causes secretory (non-inflammatory, non-bloody) diarrhea; voluminous "rice water" stools without WBCs Can lead to severe dehydration, electrolyte abnormalities, cardiac/renal failure Treatment: Oral rehydration therapy

Answer 5

Caused by streptococcus pneumoniae (alpha-hemolytic strep); optochin sensitive, gram positive diplococci Most common cause of community acquired pneumonia, especially among adults 18-65 and the elderly Presents with fever, chills, pleuritic chest pain, and cough productive of green/rusty sputum Findings: Lobar findings on physical exam - dullness to percussion, bronchial breath sounds, egophany in a focal area, lobar consolidation on CXR Treatment: Penicillins or cephalosporins; macrolides in allergic patients

Answer 6

Caused by polio virus with fecal-oral transmission Virus initially infects and replicates within the pharynx and small intestine causing fever, malaise, nausea, vomiting, an diarrhea; hematogenous spread to the CNS causes death of LMNs in the anterior horn of the spinal cord Presents with LMN signs: hypotonia, muscle weakness/flaccid paralysis, hyporeflexia, muscle atrophy; most serious complications are para/quadriplegia, respiratory muscle paralysis

Answer 7

Gram positive aerobe forming branching filaments; stains weakly acid-fast positive Normally found in soil; causes pulmonary and brain abscesses in immunocompromised patients Treated with sulfonamides *Often mistaken for TB due to pulmonary manifestations and weakly acid-fast staining

Answer 8

Dimorphic yeast - can form pseudohyphae or buds; catalase positive Common cause of mucocutaneous and systemic fungal infections including: oral/pharyngeal thrush in immunocompromised patients, vulvovaginitis, diaper rash, endocarditis in IVDUs, chronic mucocutaneous candidiasis (due to T cell deficiency), chronic granulomatous disease (due to NADPH oxidase deficiency) Treated with Nystatin (topical) or amphotericin (systemic)

Answer 9

Transmitted from infected mother to newborn upon passage through the birth canal Presents in the newborn several days - several weeks after birth with swollen eyelids, conjunctival inflammation, and purulent discharge Treated prophylactically with erythromycin eye drops

Answer 10

Most common cause of bronchiolitis and pneumonia in children; most children have been exposed by age 2 Presents with cough, tachypnea, low grade fever, and mildly decreased O2 sat; crackles and expiratory wheezes heard on auscultation Dx: Rapid serological test for viral antigen

Answer 11

Cause of fungal pneumonia in immunocompromised (neutropenic) patients; due to Aspergillus fumigatus Presents with pleuritic chest pain, cough, hemoptysis, and dyspnea

Answer 12

Caused by Rubeola (paramyxovirus) Initially presents as cough, coryza (acute inflammation of the upper respiratory mucosa), and conjunctivitis + characteristic red, maculo-papular rash which spreads from the head downward; + Koplik (blue/white) spots of buccal mucosa Complications: Acute disseminated (post-infectious) encephalomyelitis Subacute sclerosing panencephalitis Live-attenuated vaccine available

Answer 13

Occurs as a rare complication of Rubeola (measles) infection Causes multifocal inflammation and de-myelination of white matter in the brain and CNS; auto-immune mediated Similar to MS but occurs as a single episode with fever and loss of consciousness

Answer 14

Occurs as a result of long-standing infection with measles (Rubeola virus) Stage 1 - Behavior/personality changes, decreased memory Stage 2 - Myoclonic spasms, increasing memory impairment Stage 3 - Blindness, mutism, coma; fatal Can be chronically managed (not cured) in Stage 1 with interferon, Ribavirin

Answer 15

Caused by gram negative rod bordatella pertussis Produces pertussis toxin; toxin inhibits Gi, leading to overactivity of adenylate cyclase with increased production of cAMP; this leads to inhibition of phagocytosis and survival of the microbe Presents as cough on expiration and "whooping" on inspiration

Answer 16

Caused by N. meningidites - 2nd most common causative organism in young adults Presents with headache, malaise, pain with flexion and extension of the neck, + petechial / maculopapular rash on the extremities (with meningococcemia) Labs: CSF shows elevated WBCs (primarily neutrophils), elevated protein, low glucose Diagnosed by CSF culture on Thayer-Martin agar

Answer 17

Caused by the gram positive rod Corynebacterium diptheriae via a pro-phage encoded exotoxin which inhibits protein synthesis via ADP-ribosylation of EF-2 Presents with pseudomembranous pharyngitis, cervical lymphadenopathy, dysphagia Toxoid vaccine preventable

Answer 18

Caused by the poxvirus Presents as flesh-colored nodules Transmitted to the trunk by swimming pools and towels (especially in kids) or to the genitals by sexual contact

Answer 19

AKA "Swimmer's Ear," often caused by Pseudomonas Presents with ear pain, fever, erythema and tenderness of the external auricle and mandibular area

Answer 20

An opportunistic infection caused by re-activation of latent JC virus in the CNS Seen in advanced AIDS patients with CD4 < 200; causes destruction of oligodendrocytes with demyelination of white matter Presents with initial visual field deficits, mental status changes, and weakness; progresses to blindness, dementia, coma, and death within 6 months CSF fluid analysis is unremarkable; MRI shows non-enhancing lesions

Answer 21

Caused by Gardernella vaginalis infection - gram-variable, pleomorphic rod Presents as gray vaginal discharge with a fishy odor; associated with sexual activity but NOT sexually transmitted Microscopy shows clue cells Treated with metronidazole or clindamycin

Answer 22

Non-septate, branching fungal infection of the nasal cavity and sinuses Seen mostly in ketoacidotic patients due to increased concentrations of glucose and ketones Presents with headache, fever, facial pain, nasal discharge Risk of meningitis if fungi penetrate through cribiform plate into CSF space Treated with Amphotericin B

Answer 23

RNA Hepevirus; transmitted via fecal-oral route, common in Sub-Saharan Africa Presents acutely with nausea, vomiting, and abdominal pain associated with low-grade fever High mortality in pregnant women

Answer 24

Caused by release of TSST-1 toxin by S. aureus; TSST-1 is a super-antigen that non-specifically cross-links MHCII and TCR leading to clonal T-cell proliferation with massive release of IFN-y and IL-2 Presnts with fever, hypotension, desquamating rash, and end organ damage

Answer 25

A paramyxovirus clasically infecting the parotid glands and testes Presents with swollen neck and parotid glands, orchitis, and asceptic meningitis; risk of infertility, especially after puberty

Answer 26

Intracellular, gram negative coccobacilli; acid fast Enters the body through contaminated milk or direct contact with infected live stock Presents with undulating fever, weakness, loss of appetite

Answer 27

Caused by intracellular, gram negative rod Francisella Tularensis; carried by rabbits, transmitted to humans by flea or tick bite Presents as a well-demarcated, ulcerative lesion with a black base

Answer 28

Gram positive anaerobe found in normal oral flora Causes orofacial abscesses which drain yellow pus that demonstrates "sulfur granules" Treated with IV penacillin x 2-4 weeks followed by oral penicillin or amoxicillin x 6-12 months

Answer 29

Due to an arthropod-transmitted Flavivirus; most commonly seen in the Mississippi River Valley Most common cause of epidemic encephalitis in the US; also causes meningitis Treatment is supportive; no specific antiviral medications exist

Answer 30

Caused by South American protozoa Trypanosoma cruzi; transmitted by the painless bite of the Reduviid bug ("kissing bug") Presents as dilated cardiomyopathy, megacolon, megaesophagus Romana sign characteristic of acute phase

Infectious Disease - Diseases Flashcards

(54 cards)