CRIBS Group A6: Brown, Carrier, Cronin, Hayat, Hyman Clinical Manifestations of Gonorrhea, Syphilis, and Chlamydia. Q1:

lyricalwillingΜηχανική

22 Φεβ 2014 (πριν από 3 χρόνια και 6 μήνες)

61 εμφανίσεις

CRIBS

Group A6: Brown, Carrier, Cronin, Hayat, Hyman

Clinical Manifestations of Gonorrhea, Syphilis, and Chlamydia.


Q1:


A 32y/o businessman comes into your office.


He was well until yesterday,
when he admits he experienced dysuria accompanied by yellowish urethral
discharge. He also admits that he had intercourse with a prostitute 5 nights ago. You
perform a gram stain on

a specimen of the discharge and see gram
-
negative
diplococci within neutrophils.


Given this characteristic finding, you know right
away that the most likely cause of this infection is?













A:

Neisseria gonorrhoeae













B.

Proteus mirabilis













C.

Klebsiella pneumoniae













D.

Chlamydia trachomatis













E.

Treponema pallidum

Answer: (A)
.


Neisseriae are gram
-
negative, oxidase
-
positive cocci that resemble
paired kidney beans.


N. gonorrhoeae

causes gonorrhea, neonatal co
njunctivitis, &
PID. Gonorrhea in men is characterized primarily by urethritis accompanied by
dysuria and a purulent discharge. In women, infection is located primarily in the
endocervix, causing a purulent vaginal discharge and intermenstrual bleeding
(ce
rvicitis).


The most common complication in women is ascending infection into
the uterine tubes, causing salpingitis/PID, which can result in sterility or ectopic
pregnancy.


Disseminated infections commonly manifest as arthritis, tenosynovitis,
or pustule
s.


In men, the finding of gram
-
negative diplococci within PMNs is
sufficient for diagnosis. In women, the use of gram stain alone can be difficult to
interpret, so cultures should be done additionally.

T. pallidum

is a spirochete, which is a thin
-
walled,
flexible, spiral
-
shaped, motile rod.
They are so thin that they are seen only by darkfield microscopy, silver
impregnation, or immunofluorescence.

Chlamydiae

are obligate intracellular bacteria, and thus, the gram stain is not useful.
In men,

C. trachomati
s

is a common cause of NGU, which may progress to
epididymitis, prostatitis, or proctitis. In women, cervicitis develops and may
progress to PID or salpingitis.

Source: Ex Master USMLE
-
style Question Bank



Q2:

A 30
-
year
-
old, sexually active woman has had

a mucopurulent vaginal discharge
for 1 week. On pelvic examination, the

cervix appears reddened around the os, but
no erosions or mass lesions are present. A Pap smear shows numerous neutrophils,
but no dysplastic cells. A cervical biopsy specimen shows m
arked follicular
cervicitis. Which of the following infectious agents is most likely to produce these
findings?




A.

Chlamydia trachomatis




B.

Candida albicans




C.

Gardnerella vaginalis




D. HPV




E.

Neisseria gonorrhoeae




F.

Trichomonas vaginalis

Answer:

(A)

The redness of the cervix, the inflammatory cells in the cervical
discharge, and the biopsy findings indicate that the

patient has cervicitis.

Chlamydia
trachomatis

is the most common cause of cervicitis in sexually active women.
Candidiasis,
gonorrhea, and trichomoniasis also are common. Candidiasis often
produces a scant, white, curdlike vaginal discharge; gonorrhea may have an
associated urethritis; and

Trichomonas

may produce a profuse homogeneous,
frothy, and adherent yellow or green vagin
al discharge.

Gardnerella

is found in
bacterial vaginosis, a common condition caused by overgrowth of
bacteria.

Gardnerella

infection produces a moderate, homogeneous, low
-
viscosity,
adherent vaginal discharge that is white or gray and has a characteristic

“fishy”
odor; “clue” cells are seen on a wet mount. Herpetic infections are more likely to
manifest as clear vesicles on the skin in the perineal region. Infection with human
papillomavirus is associated with condylomata, dysplasias, and carcinoma.

Source
: Robbins & Cotran Review of Pathology, 3
rd

ed, Ch.22
-

The Female
Genital Tract



Q3:

A 73
-
year
-
old man who has had progressive dementia for the past 6 years dies
of bronchopneumonia. Autopsy shows that the thoracic aorta has a dilated root and
arch, givi
ng the intimal surface a “tree
-
bark” appearance. Microscopic examination
of the aorta shows an obliterative endarteritis of the vasa vasorum. Which of the
following laboratory findings is most likely to be recorded in this patient's medical

history?









A. High double
-
stranded DNA titer








B. P
-
ANCA positive 1:1024








C. Sedimentation rate 105 mm/hr








D. Ketonuria 4+








E. Antibodies against Treponema pallidum


Answer:

(E) This description is most suggestive of syphilitic

aortitis, a c
omplication of tertiary syphilis, with characteristic

involvement of the thoracic aorta. Obliterative endarteritis is not a

feature of other forms of vasculitis. High
-
titer doublestranded DNA

antibodies are diagnostic of systemic lupus erythematosus, and a

test

result for P
-
ANCA is positive in various vasculitides, including

microscopic polyangiitis. A high sedimentation rate is a nonspecific

marker of inflammatory diseases. Ketonuria can occur in individuals

with diabetic ketoacidosis.


Source: Robbins & C
otran Review of Pathology, 3rd ed, Ch.11
-
Blood Vessels



Q4:


A sexually active, 26
-
year
-
old man has had pain on urination for the past 4 days.
On physical examination, there are no lesions on the penis. He is afebrile. Urinalysis
shows no blood, ketones,
protein, or glucose. Microscopic examination of the urine
shows few WBCs and no casts or crystals. What infectious agent is most likely to
produce these findings?

















A.

Chlamydia trachomatis

















B.

Mycobacterium tuberculosis

















C. Herpes simplex virus

















D.

Candida albicans

















E.

Treponema pallidum




Answer:

(A)

This patient has urethritis. The most common cause of nongonococcal
urethritis in men is

Chlamydia trachomatis
. The condition is a
nuisance; however,
the behavior that led to the infection can place the patient at risk of other sexually
transmitted diseases. Tuberculosis of the urinary tract is uncommon. Herpes
simplex can produce painful vesicles on the skin.

Candida

infections typic
ally occur
in immunocompromised patients or in patients receiving long
-
term antibiotic
therapy. A syphilitic chancre on the penis is an indicator of

Treponema
pallidum

infection.

Source: Robbins & Cotran Review of Pathology, 3
rd

ed, Ch.20
-

The Kidney



Q5:

A 20
-
year
-
old man who has multiple sexual partners and does not use barrier
precautions comes to the physician complaining of a nontender ulcer on the penis
that has been present for 1 week. On physical examination, the 0.6
-
cm lesion has a
firm, erythema
tous base and sharply demarcated borders. The lesion is scraped, and
darkfield examination is positive for spirochetes consistent with
Treponema
pallidum
. Which of the following is most likely to be seen microscopically in the
biopsy specimen?


A. Granulom
atous inflammation with suppuration


B. Granulomatous inflammation with caseation


C. Acute inflammation with abscess formation


D. Perivascular inflammation with plasma cells


E. Gummatous inflammation


Answer:

(D)
Syphilitic chancres occur in the primary

stage of syphilis and are
characterized by lymphoplasmacytic infiltrates and by an obliterative endarteritis.
Similar lesions also may appear with secondary syphilitic mucocutaneous lesions.
Suppurative granulomas are typical of cat
-
scratch disease. Casea
ting granulomatous
inflammation is more characteristic of tuberculosis or fungal infections. Acute
inflammation with abscess formation is characteristic of bacterial infections such as
gonorrhea. Gummatous inflammation can be seen in adults with tertiary s
yphilis or
in congenital syphilis.

Source: Robbins & Cotran Review of Pathology, 3
rd

ed, Ch.8
-
Infectious Diseases