Systems based Microbiology Flashcards
1
Q
What 2 protozoa are most likely to cause watery diarrhea?
A
Giardia and Cryptosporidium
2
Q
What is the likely source of multiple brain abscesses?
A
Bacteremia
3
Q
What causes of pneumonia are associated with intravenous drug use?
A
Streptococcus pneumoniae, Staphylococcus aureus
4
Q
Which species of Chlamydia causes pneumonia in children younger than 3 years of age, and which causes it in school-aged children?
A
Chlamydia trachomatis in children younger than 3 years of age; Chlamydia pneumoniae in school-aged children
5
Q
Which white blood cell type predominates in cerebrospinal fluid in bacterial, fungal, and viral meningitis?
A
Polymorphonuclear leukocytes (PMNs) in bacterial meningitis and lymphocytes in fungal and viral meningitis
6
Q
Infection by which 2 organisms is most commonly linked to brain abscesses?
A
Viridans streptococci and Staphylococcus aureus
7
Q
What microorganism is associated with food poisoning from reheated rice?
A
Bacillus cereus; “Food poisoning from reheated rice? Be serious! (B cereus)”
8
Q
What is the mode of transmission of a TORCH infection?
A
Transmission of a microbe from mother to fetus; usually transplacental but can also occur during vaginal delivery (eg, HSV-2)
9
Q
What constellation of findings may be seen in a congenital rubella infection?
A
Classic triad: eye abnormalities (eg, cataracts), ear issues (eg, deafness), congenital heart disease (eg, PDA) ± a “blueberry muffin” rash (“I [eye] ♥ ruby [rubella] earrings”)
10
Q
What organism uniquely causes pneumonia in patients with HIV?
A
Pneumocystis jirovecii
11
Q
What childhood rash presents with a high fever for several days followed by diffuse rose-colored macules?
A
Roseola (exanthem subitum) caused by human herpesvirus 6 infection; can present with febrile seizures
12
Q
What causes of pneumonia are associated with alcohol overuse?
A
Klebsiella and anaerobes secondary to aspiration (eg, Fusobacterium, Peptostreptococcus, Prevotella, Bacteroides)
13
Q
What feature of enterohemorrhagic Escherichia coli causes bloody diarrhea and hemolytic-uremic syndrome?
A
Shiga-like toxin, produced by enterohemorrhagic E coli O157:H7
14
Q
How does congenital HIV infection present?
A
Recurrent infections or chronic diarrhea
15
Q
What organisms cause condyloma acuminata and condyloma lata, respectively?
A
Human papillomaviruses 6 and 11 cause condyloma acuminata, andTreponema pallidum causes condyloma lata
16
Q
What childhood rash presents with pink macules and papules that start on the head and spread to the body and postauricular lymph nodes?
A
Rubella (caused by the rubella virus); the rash eventually desquamates
17
Q
Which vaginal infections present with a vaginal pH > 4.5?
A
Bacterial vaginosis and Trichomonas vaginitis
18
Q
In sexually active individuals, which pathogen commonly causes septic arthritis and rarely causes osteomyelitis?
A
Neisseria gonorrhoeae
19
Q
What is the character of the sputum produced by patients with aspiration pneumonia?
A
Purulent and malodorous
20
Q
How does cytomegalovirus infection present in a pregnant patient?
A
It is usually asymptomatic; in rare cases, mononucleosis-like symptoms may be present
21
Q
What pathogen is higher risk in unvaccinated individuals and presents with low-grade fever and coryza progressing to cough with posttussive emesis?
A
Bordetella pertussis
22
Q
What part of the body does Staphylococcus aureus normally colonize?
A
The nose
23
Q
What aspects of Enterococcus infections make them particularly difficult to treat?
A
They are often drug resistant and nosocomial
24
Q
What organisms most commonly cause meningitis in newborns and infants up to 6 months of age?
A
Group B Streptococcus, Escherichia coli, and Listeria
25
What organism is the most common cause of osteomyelitis?
Staphylococcus aureus (assume this cause if information is limited)
26
What vaginal infection presents with a "strawberry cervix" and frothy, foul-smelling, green-yellow discharge?
Trichomonas vaginitis
27
A patient in the intensive care unit who has been intubated for 1 week shows ↑ sputum production on suctioning. A chest x-ray shows new infiltrates. Likely diagnosis?
Ventilator-associated pneumonia from Pseudomonas aeruginosa, Klebsiella, Acinetobacter, or Staphylococcus aureus (late onset)
28
What is the most common cause of diarrhea in developed countries?
Norovirus
29
How does congenital syphilis infection present if the baby survives?
Facial abnormalities (notched teeth, saddle nose, short maxilla), cranial nerve VIII deafness, saber shins
30
What are the nonspecific signs common to many ToRCHHeS infections?
Most include hepatosplenomegaly, thrombocytopenia, jaundice, and growth retardation
31
Which 2 organisms are common causes of pneumonia in neonates (\< 4 weeks old)?
Group B streptococci and Escherichia coli
32
Why are urinary tract infections 10 times more common in females than in males?
Females have shorter urethras, which can be colonized by fecal flora
33
What is the pathophysiology of lymphogranuloma venereum?
Infection of the lymphatics caused by Chlamydia trachomatis (L1-L3)
34
Name the 6 organisms (microbes that pass from mother to fetus) that cause the TORCH infections.
ToRCHHeS: Toxoplasma gondii, Rubella, Cytomegalovirus, HIV, Herpes simplex virus type 2, Syphilis
35
A patient with meningitis has an ↑ opening pressure on lumbar puncture. Cerebrospinal fluid analysis shows ↑ protein, ↓ glucose, and a lymphocytic pleocytosis. Diagnosis?
Fungal or tuberculosis-induced meningitis
36
What 2 toxins are produced by enterotoxigenic Escherichia coli
LT (heat-labile) and ST (heat-stable) toxins
37
What are 2 causes of painful genital ulcers?
Chancroid caused by Haemophilus ducreyi (it’s so painful, you do cry) and genital herpes caused by HSV-2
38
In a child with aToxoplasma gondii infection, what finding in addition to the classic triad of manifestations might be observed?
A “blueberry muffin" rash may accompany the triad of hydrocephalus, chorioretinitis, and intracranial calcifications
39
What are some of the ways that the spastic paralysis of Clostridium tetani infection may present?
Lockjaw (trismus), opisthotonus
40
What organisms are associated with postviral causes of pneumonia?
Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae
41
What risk factors predispose a patient to Clostridium difficile infection?
Recent antibiotic use or hospitalization
42
What microorganism is associated with a food-borne illness from meats, mayonnaise, and custards?
Stapylococcus aureus, which produces preformed toxins
43
What are the initial steps in treatment of a patient with suspected meningitis?
Give ceftriaxone and vancomycin empirically; if Listeria is suspected, add ampicillin
44
What fungal organisms cause meningitis and are associated with HIV?
Cryptococcus species
45
What clinical features are seen in the mother of an infant withToxoplasma gondii infection?
The mother is usually asymptomatic and rarely has lymphadenopathy
46
What sexually transmitted infection has a high risk for opportunistic infections, Kaposi sarcoma, and lymphoma?
HIV
47
In which part of the body are viridans streptococci considered normal flora?
The oropharynx
48
What sexually transmitted infection may present with conjunctivitis, urethritis, cervicitis, epididymitis, pelvic inflammatory disease, and reactive arthritis?
Chlamydia
49
How does genital herpes present?
Painful penile, vulvar, or cervical ulcers and vesicles
50
What pathogen is higher risk in unvaccinated individuals and presents with pharyngitis and grayish psuedomembranes that may cause airway obstruction?
Corynebacterium diphtheriae
51
What microscopic findings are seen with Candida vulvovaginitis?
Pseudohyphae
52
What is the cutaneous manifestation of erythema infectiosum (fifth disease)?
The classic "slapped cheek" rash that appears on the face (this is parvovirus B19 infection)
53
How has the incidence of meningitis caused by Haemophilus influenzae changed over time?
Decreased as a result of conjugate H influenzae vaccinations
54
Vertebral osteomyelitis can be uniquely caused by which organisms?
Mycobacterium tuberculosis in Pott disease (Staphylococcus aureus is another cause)
55
What pathogens are associated with infection related to urinary catheterization?
Proteus spp, Escherichia coli, Klebsiella (PEcK)
56
What causes of brain abscesses are associated with preceding dental infection or extraction?
Oral anaerobes
57
What organism that causes urinary tract infection is associated with the formation of struvite stones?
Proteus mirabilis
58
What organism is the second most common cause of urinary tract infections in sexually active females?
Staphylococcus saprophyticus
59
What sexually transmitted infection presents with a painless, beefy red ulcerative genital lesion that bleeds on contact?
Donovanosis (or granuloma inguinale) caused by Klebsiella (Calymmatobacterium) granulomatis
60
What organism is likely responsible for a brain abscess in a patient with AIDS and a CD4+ count \<100 cells/mm3?
Toxoplasma (a reactivation)
61
What organism that causes urinary tract infections is associated with a large mucoid capsule and viscous colonies?
Klebsiella pneumoniae
62
What pathogens are associated with atypical pneumonia?
Chlamydophila, Mycoplasma, Legionella, and viruses (respiratory syncytial virus, cytomegalovirus, influenza, adenovirus)
63
What bacteria are typically found in dental plaque?
Streptococcus mutans
64
A baby is born with hydrocephalus, chorioretinitis, and intracranial calcifications. What is the causative organism?
Toxoplasma gondii
65
What are the most likely causes of pneumonia in the elderly (\>65 years of age) population?
Streptococcus pneumoniae, influenza virus, anaerobes, Haemophilus influenzae, and gram-negative rods
66
Which 2 bacteria are considered part of the normal flora in the colon?
Bacteroides fragilis and, to a lesser extent, Escherichia coli
67
What is the mechanism of cytomegalovirus transmission?
Sexual contact or organ transplantation
68
What is the most common source of Vibrio cholerae diarrhea?
Infected seafood
69
Name the 4 common bacterial organisms that can cause watery diarrhea.
Clostridium difficile, Clostridium perfringens, enterotoxigenic Escherichia coli, and Vibrio cholerae
70
Name 5 viral causes of meningitis.
Enteroviruses (particularly coxsackievirus), herpes simplex virus-2 (HSV-2), HIV, West Nile virus (which can result in encephalitis), varicella-zoster virus (VZV)
71
What pathogen resides in the nasopharynx and causes meningitis in unvaccinated children?
Haemophilus influenzae type b
72
When performing lumbar puncture, what are the opening pressure levels expected in bacterial, fungal, and viral meningitis, respectively?
Increased in both bacterial and fungal meningitis, while normal or increased in viral meningitis
73
What microorganism is associated with a food-borne illness from deli meats or soft cheeses?
Listeria monocytogenes
74
Name the most common causes of pneumonia in adults 40 to 65 years of age.
Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma, anaerobes, viruses
75
A patient with meningitis has ↑ opening pressure on lumbar puncture. Cerebrospinal fluid analysis shows ↑ protein, ↓ glucose, and a neutrophilic pleocytosis. Diagnosis?
Bacterial meningitis
76
What sexually transmitted infection may result in jaundice?
Hepatitis caused by hepatitis B virus
77
What species of bacteria that causes urinary tract infections grows with strong, pink lactose fermentation on MacConkey agar?
Escherichia coli
78
Where in the central nervous system does an abscess due to sinusitis or a dental infection typically present?
Frontal lobe
79
What 2 microorganisms are associated with a quick onset and a quick resolution of food poisoning?
Staphylococcus aureus and Bacillus cereus cause food poisoning that is quick to start and brief in duration
80
What are some signs and symptoms commonly seen in Legionella infection?
Signs of pneumonia, neurologic abnormalities, and gastrointestinal symptoms (eg, diarrhea, nausea, vomiting)
81
What organism is associated with pseudomembranous colitis and watery diarrhea?
Clostridium difficile
82
What organisms are the most likely causes of meningitis in patients aged 6 to 60 years?
Streptococcus pneumoniae, Neisseria meningitidis, enteroviruses, and herpes simplex virus
83
Which 2 organisms are likely causes of osteomyelitis in patients with prosthetic joint replacements?
Staphylococcus aureus and Staphylococcus epidermidis
84
What constellation of findings is seen in patients with congenital cytomegalovirus infection?
Hearing loss, seizures, chorioretinitis, "blueberry muffin" rash, petechial rash, and periventricular calcifications
85
Name the 4 types of infectious process that make up pelvic inflammatory disease.
Salpingitis, endometritis, hydrosalpinx, and tubo-ovarian abscess
86
What is the test of choice for the diagnosis of acute osteomyelitis?
MRI (details sites that are involved)
87
Why has the incidence of group B streptococcal meningitis decreased in neonates?
Because of screening and antibiotic prophylaxis during pregnancy
88
Which diagnostic marker of urinary tract infections indicates evidence of WBC activity?
Leukocyte esterase
89
What sexually transmitted infection may present with urethritis, cervicitis, pelvic inflammatory disease, creamy purulent discharge, prostatitis, epididymitis, or arthritis?
Gonorrhea caused by Neisseria gonorrhoeae
90
What group of drugs is used in the treatment of Candida vulvovaginitis?
Azoles
91
Where in the central nervous system does an abscess resulting from otitis media or mastoiditis typically present?
Temporal lobe and cerebellum
92
What pathogen is higher risk in unvaccinated individuals and presents with fever, drooling, dysphagia, and difficulty breathing due to edema?
Haemophilus influenzae type b causing epiglottitis (can affect immunized and unimmunized children)
93
What 2 organisms commonly cause osteomyelitis in patients with sickle cell disease?
Salmonella and Staphylococcus aureus
94
What food sources are commonly associated with a Salmonella infection?
Most likely poultry or eggs
95
What is the mechanism of transmission of herpes simplex virus 2?
Contact with skin or mucous membranes
96
Osteomyelitis from cat or dog bites is most frequently caused by which organism?
Pasteurella multocida
97
What is the cause of decreased incidence of rotavirus infections in developed countries?
Vaccination
98
What organism can cause both bloody diarrhea and liver abscesses?
Entamoeba histolytica, a protozoan that causes amebic dysentery
99
What species of bacteria is the leading cause of urinary tract infections?
Escherichia coli
100
What is the likely source of a single brain abscess?
Spread of infection from contiguous sites
101
What bacteria are considered normal flora in the vagina?
Lactobacillus, Escherichia coli, and group B streptococcus
102
Which comma- or S-shaped organism grows at 42 °C and causes bloody diarrhea?
Campylobacter
103
What are the most likely causes of meningitis in children 6 months to 6 years of age?
Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae type B, group B Streptococcus, and enteroviruses
104
Name 2 classes of drugs that are associated with a Clostridium difficile infection.
Antibiotics and proton pump inhibitors
105
What is the cause of amebic dysentery vs bacillary dysentery?
Amebic dysentery: Entamoeba histolytica; bacillary dysentery: Shigella
106
What are the most common symptom and the most common laboratory finding seen with Clostridium difficile infection?
Watery diarrhea and leukocytosis
107
Which infectious agents are the most common causes of pneumonia in the immunocompromised?
Staphylococcus aureus, Pneumocystis jirovecii (with HIV), enteric gram ⊖ rods, fungi, and viruses
108
Which organisms commonly cause pneumonia in patients with chronic obstructive pulmonary disease?
Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Pseudomonas
109
What is the most common route of transmission for microbes that cause urinary tract infections?
Bacteria from the urethra ascends to the bladder
110
What are the 2 most common causes of nosocomial infections?
Escherichia coli (urinary tract infections) and Staphylococcus aureus (wound infections)
111
What sexually transmitted infection presents with exudative, painful genital ulcers and inguinal lymphadenopathy?
Chancroid caused by Haemophilus ducreyi (it’s so painful, you do cry)
112
How does a rubella infection typically present in a pregnant patient?
Rash, polyarthritis, polyarthralgia, and lymphadenopathy
113
Which organism that causes urinary tract infections is characterized by production of a red pigment?
Serratia marcescens
114
How sensitive and specific are erythrocyte sedimentation rate and C-reactive protein laboratory assays in the workup for osteomyelitis?
Elevated values are sensitive but not specific for osteomyelitis
115
What microorganism may cause a food-borne illness as well as wound infections from contact with contaminated shellfish or water?
Vibrio vulnificus
116
How does maternal herpes simplex virus type 2 infection present?
Either without symptoms or with herpetic (vesicular) lesions
117
What complications may be seen with a congenital herpes simplex virus type 2 infection?
Meningoencephalitis and herpetic vesicular lesions
118
What pathogen is higher risk in unvaccinated individuals and presents with meningitis, myalgia, and paralysis?
Poliovirus
119
What are the common signs and symptoms of pyelonephritis?
Fevers, chills, costovertebral angle tenderness, flank pain, hematuria
120
What are some of the complications of salpingitis?
Adhesions, ectopic pregnancy, infertility, chronic pelvic pain
121
What microscopic findings are seen with Trichomonas vaginitis
Motile trichomonads (pear shaped)
122
What organism is associated with bloody diarrhea and pseudoappendicitis?
Yersinia enterocolitica
123
What is the treatment of choice for bacterial vaginosis?
Metronidazole or clindamycin
124
What pathogens are likely responsible for nosocomial infections associated with decubitus ulcers, surgical wounds, or drains?
Staphylococcus aureus (including MRSA) or gram-negative anaerobes (eg, Prevotella, Bacteroides, Fusobacterium)
125
What organism leads to chancroid?
Haemophilus ducreyi
126
What are the dermatologic manifestations of a congenital cytomegalovirus infection?
Petechial rash, “blueberry muffin” rash
127
Which stage of syphilis presents with fever, skin rashes, lymphadenopathy, and condyloma lata?
Secondary syphilis
128
Is a neonate delivered via cesarean section colonized with bacteria at the time of birth?
No; neonates delivered by cesarean section are born without any flora but are colonized quickly after birth
129
What virus is associated with genital herpes?
Herpes simplex virus 2 (also herpes simplex virus 1 but less commonly)
130
What organism that causes urinary tract infections is associated with "swarming" on agar due to motility?
Proteus mirabilis
131
What pathogen is higher risk in unvaccinated individuals and presents with postauricular lymphadenopathy and a descending rash?
Rubella virus
132
How is rubella typically acquired?
Respiratory droplets
133
What microorganism is associated with a food-borne illness from undercooked meat?
Escherichia coli O157:H7
134
What are the glucose levels in cerebrospinal fluid in bacterial, fungal, and viral meningitis?
Decreased in bacterial and fungal; normal in viral
135
What does a positive urine nitrite test result indicate?
Reduction of nitrates in urine by gram-negative bacteria such as Escherichia coli
136
What pathogens are associated with infections related to mechanical ventilation or endotracheal intubation?
Pseudomonas aeruginosa, Klebsiella, Acinetobacter, Staphylococcus aureus
137
What microorganism is associated with a food-borne illness from reheated meat?
Clostridium perfringens
138
What organism causes both watery diarrhea and gas gangrene?
Clostridium perfringens
139
What sexually transmitted infection presents with vaginitis and a strawberry-colored cervix?
Trichomoniasis caused by Trichomonas vaginalis
140
What 3 microbes, other than ToRCHHeS, can be causes of neonatal infection or hydrops fetalis?
Streptococcus agalactiae (group B streptococci), Escherichia coli, and Listeria monocytogenes can cause meningitis in neonates; parvovirus B19 can lead to hydrops fetalis
141
What pathogen is associated with infection related to water aerosols?
Legionella
142
What diagnostic test is used to identify the organisms in osteomyelitis?
Culture of specimen obtained via biopsy or aspiration
143
How is Toxoplasma gondii characteristically transmitted?
Through cat feces or ingestion of undercooked meat
144
What characteristic x-ray findings may be seen after aspiration?
Infiltrates in the right lower lobe (or right upper or middle lobe if the patient is recumbent)
145
Which comma-shaped organisms cause rice-water stools?
Vibrio cholerae
146
Which of the TORCH infections often results in stillbirth or hydrops fetalis?
Syphilis
147
Name the most common causes of pneumonia in adults 18 to 40 years of age.
Mycoplasma, Chlamydia pneumoniae, Streptococcus pneumoniae, viruses (eg, influenza)
148
What organisms are associated with nosocomial pneumonia?
Staphylococcus aureus, Pseudomonas, and enteric gram-negative rods
149
What organisms commonly cause osteomyelitis associated with intravenous drug use?
Staphylococcus aureus (most common), Pseudomonas, Candida
150
Which risk factors are associated with hepatitis B and hepatitis C nosocomial infections?
Renal dialysis provided in a dialysis unit, needlesticks
151
Why does Staphylococcus aureus cause food poisoning quickly?
The toxins that cause the food poisoning are preformed
152
What features are seen in infection caused by mechanical ventilation or endotracheal intubation?
New infiltrate on chest x-ray, increased sputum production (with a sweet odor if due to Pseudomonas)
153
Which components of Clostridium botulinum are associated with a food-borne illness from consumption of improperly canned foods vs raw honey?
Improperly canned foods: toxins of C botulinum; raw honey: spores of C botulinum
154
What are the protein levels in cerebrospinal fluid in bacterial, fungal, and viral meningitis?
Increased in bacterial and fungal; normal to increased in viral
155
What sexually transmitted infection is characterized by genital warts and koilocytes?
Condyloma acuminata
156
What is the vaginal pH in Candida vulvovaginitis?
Normal (4.0-4.5)
157
Which microorganisms are associated with aspiration pneumonia?
Polymicrobial, gram-negative bacteria (often anaerobes)
158
Name the most common causes of pneumonia in patients who are 4 weeks to 18 years of age.
Viruses (respiratory syncytial virus [RSV]), Mycoplasma, Chlamydia trachomatis, Chlamydia pneumoniae, Streptococcus pneumoniae (Runts May Cough Chunky Sputum)
159
When will a urease test result be positive for a patient with a urinary tract infection?
When the infection is due to a urease-producing organism (eg, Proteus mirabilis)
160
What pathogens are likely responsible for infections related to intravascular catheters?
Staphylococcus aureus (including MRSA), Staphylococcus epidermidis (from long-term use)
161
What finding on urinalysis can help to distinguish a urinary tract infection from pyelonephritis?
Detection of WBC casts (absent in a urinary tract infection, present in pyleonephritis)
162
Name some of the common predisposing factors for urinary tract infections.
Female sex, obstruction (kidney stones, enlarged prostate), catheterization, kidney surgery, congenital genitourinary malformation (eg, vesicoureteral reflux), pregnancy, diabetes
163
What are the most likely causes of meningitis in patients older than 60 years?
Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae type b, group B Streptococcus, Listeria
164
What microorganisms are associated with a food-borne illness from raw and undercooked seafood?
Vibrio parahaemolyticus and Vibrio vulnificus
165
What are the 3 congenitally acquired TORCH infections in which the pregnant patient is usually asymptomatic?
Toxoplasma gondii, cytomegalovirus, and herpes simplex virus type 2
166
Which organisms cause pneumonia in patients with cystic fibrosis?
Pseudomonas, Burkholderia cepacia, Staphylococcus aureus, Streptococcus pneumoniae
167
What are the common signs and symptoms of cystitis?
Dysuria, suprapubic pain, urinary frequency and urgency, urinalysis positive for white blood cells (but not their casts)
168
What organism that causes urinary tract infection is associated with a fruity odor and blue-green tint?
Pseudomonas aeruginosa, often acquired nosocomially
169
What lactose-negative bacterium with a low median infective dose (ID50) is associated with bloody diarrhea?
Shigella
170
Pelvic inflammatory disease is most often caused by which 2 organisms?
Chlamydia trachomatis (subacute, often undiagnosed) and Neisseria gonorrhoeae (acute)
171
What characteristic microscopic finding is associated with bacterial vaginosis?
Clue cells
172
What is a life-threatening fetal complication caused by exposure to parvovirus B19 during pregnancy?
Hydrops fetalis
173
What is seen on a wet prep performed for a patient with trichomoniasis?
Motile trichomonads
174
How does enteroinvasive Escherichia coli cause diarrhea?
By invasion of the colonic mucosa
175
Which 3 viruses cause watery diarrhea?
Rotavirus, enteric adenovirus, and norovirus
176
Staphylococcus epidermidis is part of the normal flora of what 2 parts of the body?
The skin and the nose
177
In addition to painful genital lesions, herpes simplex virus type 2 commonly causes what systemic symptoms?
Headaches, fevers, myalgia (herpes simplex virus-1 may also cause these symptoms, but not as commonly)
178
What childhood rash presents with cough, conjunctivitis, coryza, and bluish spots on the buccal mucosa followed by a descending confluent rash?
Measles (rubeola); the blue-white spots on the buccal mucosa are known as Koplik spots
179
What is the pathophysiology behind pyelonephritis?
Ascension of bacteria to the kidneys from the bladder
180
What sexually transmitted infection presents with painful inguinal lymphadenopathy (buboes) and painless genital ulcers?
Lymphogranuloma venereum
181
What microorganism is associated with a food-borne illness from poultry, meat, and eggs?
Salmonella
182
When a pregnant patient contracts syphillis, which stages of the illness are likely to cause fetal infection?
The primary (chancre) and secondary (disseminated rash) stages
183
What pathogen is higher risk in unvaccinated individuals and presents with cough, runny nose, conjunctivitis, a diffuse rash, and blue-white spots in the mouth?
Measles virus (the mouth lesions are called Koplik spots)
184
What common vaginal infection presents without inflammation?
Bacterial vaginosis (inflammation is found with Trichomonas vaginitis ["strawberry cervix"] and Candida vulvovaginitis)
185
What causes of pneumonia are associated with aspiration?
Anaerobes
186
What are the characteristics of tertiary syphilis?
Gummas, tabes dorsalis, aortitis, general paresis, and an Argyll Robertson pupil
187
What are the reservoirs associated with Shigella vs Salmonella?
Shigella: human reservoir only; Salmonella: animal reservoirs, especially poultry and eggs
188
Why is MRI better than x-rays for the diagnosis of osteomyelitis?
MRI detects acute infection and details anatomic involvement; x-rays are insensitive in early detection but may be useful for patients with chronic osteomyelitis
189
A patient with meningitis undergoes lumbar puncture. Cerebrospinal fluid analysis shows normal protein and glucose with lymphocytic pleocytosis. Diagnosis?
Viral meningits
190
Which stage of syphilis presents with a painless chancre?
Primary syphilis
191
What pathogen is higher risk in unvaccinated individuals and presents with muscle spasms and spastic paralysis?
Clostridium tetani
192
What microscopic findings are associated with the ulcer shown in the image, which bleeds readily on contact?
Cytoplasmic Donovan bodies (the infectious agent is Klebsiella [Calymmatobacterium] granulomatis); this is granuloma inguinale (donovanosis)
193
What congenital infection presents with the CT findings shown in the image?
Cytomegalovirus infection (image shows periventricular calcifications)
194
A patient has the following exam findings: purulent cervical discharge (image), adnexal tenderness, and cervical motion tenderness. Diagnosis?
Pelvic inflammatory disease
195
A young woman presents with vaginal inflammation and a thick, white, cottage cheese–like discharge. What is your diagnosis?
Candida vulvovaginitis
196
What is the treatment of choice for a patient with the microscopic findings shown in the image?
Metronidazole for both the patient and partners; the motile, pear-shaped trichomonads indicate aTrichomonas infection
197
What childhood rash presents with a vesicular rash (image) that begins on the trunk before spreading to the face and extremities with lesions in different stages?
Chickenpox caused by the varicella-zoster virus
198
The newborn of a mother with poor prenatal care has the eye findings shown in the image, and you note a continuous heart murmur on auscultation. What infection do you suspect?
Congenital rubella, which can cause both cataracts and congenital heart disease such as patent ductus arteriosus
199
What childhood rash presents with painful oral ulcers and vesicles and oval vesicles on the palms and soles as shown in the image?
Coxsackievirus type A (this is hand-foot-mouth disease); the vesicles and ulcers in oral mucosa are referred to as herpangina
200
You examine the vagina of a woman with vaginal discomfort and note the thin, white discharge with fishy odor (image). KOH whiff test is ⊕. What is your diagnosis?
Bacterial vaginosis
201
A child, who has had a fever and sore throat, now exhibits a sandpaper-like rash (image), also seen on the trunk and extremities. What bacteria are responsible for these findings?
Streptococcus pyogenes (note the flushed cheeks and circumoral pallor in the image); strawberry tongue may also be seen (this is scarlet fever)
202
Findings on laparoscopy of a 42-year-old patient with a history of untreated STIs are shown. Parietal peritoneum adhesions to her liver are noted. Diagnosis?
Fitz-Hugh–Curtis syndrome (a complication of pelvic inflammatory disease)
203
The newborn of a mother with poor prenatal care has a rash (image). Which 3 infectious agents are in your differential diagnosis?
This is a "blueberry muffin" rash, seen in neonatal Toxoplasma gondii, rubella, and cytomegalovirus infections
