Internal-Medicine

220 10: Infection
28. (B) Adequate rest is the treatment of choice,
but forced bed rest is not necessary.
Glucocorticoids hasten defervescence and resolution
of pharyngitis but are not routinely
used. Acyclovir halts oropharyngeal shedding
of EBV but has minimal effect on the clinical
disease. Similarly alpha-interferon and ganciclovir
have antiviral efficacy but have no role to
play in uncomplicated infectious mononucleosis.
Antibiotics are not helpful, and ampicillin
is likely to cause a pruritic maculopapular rash
in most patients. (Kasper, p. 1048)
29. (C) Donovanosis, or granuloma inguinale, is
a mildly contagious, chronic, indolent disease
that can be sexually transmitted.
Calymmatobacterium granulomatis, a Gramnegative
intracellular bacterium, is felt to be
the cause. It is endemic in many tropical areas.
Daily doxycycline or weekly azithromycin
until the lesions are healed are the usual treatments.
Erythromycin is used in pregnant
patients. (Kasper, pp. 932–933)
30. (B) S. pneumoniae colonizes the nasopharynx of
5–10% of healthy adults and up to 20–40% of
children. The source of pneumococcal meningitis
is either direct extension from middle ear
or sinus infections, or via seeding from a bacteremia.
In the latter circumstance, bacteremia
from pneumonia would be more likely than
from infective endocarditis. (Kasper, pp. 807–808)
31. (C) The patient is infected with Pneumocystis
organisms invading an immunocompromised
host. The treatment of choice is trimethoprimsulfamethoxazole.
Alternate therapies include
pentamidine (highly toxic) and trimetrexate
plus folinic acid. (Kasper, p. 1195)
32. (D) All the sites mentioned can be involved by
amebiasis, but the liver is the most common.
Most travelers who develop an amebic liver
abscess will do so within a few months of their
return. Pleuropulmonary and pericardial
involvement results from extension from the
liver. (Kasper, p. 1215)
33. (D) Acute and convalescent titres of specific
IgG antibodies will confirm the diagnosis of
mumps. A single test revealing a specific IgM
antibody can also confirm the disease. Urine,
saliva, and throat swabs will grow the mumps
virus, but blood does not. Salivary amylase is
elevated but is relatively nonspecific. Of course,
a typical presentation during an epidemic
probably does not require any confirmatory
tests. Sporadic cases require more active confirmation.
Other causes of parotitis requiring
specific treatment include calculi, bacterial
infections, and drugs. Tumors, sarcoid, TB,
leukemia, Hodgkin’s disease, Sjögren’s syndrome,
and lupus erythematosus can also
cause parotid enlargement. (Kasper, p. 1155)
34. (A) Staphylococcal enterotoxin food poisoning is
characterized by violent GI upset with severe
nausea, cramps, vomiting, and diarrhea. It
occurs very rapidly after ingestion (1–6 hours)
and usually resolves by 12 hours. (Kasper, p. 819)
35. (C) The patient has tinea capitis, which may
be caused by Trichophyton or Microsporum
species. It may be successfully treated with topical
azole drugs (e.g., clotrimazole). More
severe infections are usually treated with systemic
medications. (Kasper, p. 1191)
36. (C) Coxsackie A viruses may cause a number of
syndromes, including herpangina, exanthem,
aseptic meningitis, common cold, paralysis,
pneumonitis, and summer febrile illness. It is
distinguished from HSV-1 herpes stomatitis by
the fact that most of the lesions are concentrated
in the posterior portion of the mouth
and that there is no gingivitis. The other virus
does not cause oral lesions. HSV-2 can occasionally
cause oral lesions. (Kasper, p. 1145)
37. (B) Rabies is transmitted through the saliva of
infected animals. Once clinical signs develop,
the disease is almost 100% fatal. Symptoms of
rabies may include apathy as well as hyperexcitability.
Finding Negri bodies in nerve cells of
the brain in infected animals confirms the diagnosis.
Polymerase chain reaction for detection
of viral material is another method of confirming
the diagnosis. In cats and dogs that are not
available for observation (lasting 10 days) to
determine if they have signs of rabies, public