Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (118 page)

   Gram stain of scrapings from petechial skin lesions demonstrates pathogen in approximately 70% of patients with meningococcemia; Gram stain of buffy coat of peripheral blood and, less often, peripheral blood smear may reveal this organism.

   Laboratory findings due to preceding diseases/conditions:

   Pneumonia, otitis media, sinusitis, skull fracture prior to pneumococcal meningitis

   
Neisseria
epidemics prior to clinical cases of meningitis

   Bacterial endocarditis, septicemia, and so on

   
S. pneumoniae
in alcoholism, myeloma, sickle cell anemia, splenectomy, immunocompromised state

   
Cryptococcus
and
M. tuberculosis
in steroid therapy and immunocompromised state

   Gram-negative bacilli in immunocompromised state

   
H. influenzae
in splenectomy

   Lyme disease

   Primary diagnostic testing may also include other laboratory diagnostic tests for a patient in whom clinical presentation, epidemiologic risk factors, or signs and symptoms suggest a high prior probability of a pathogen outside the normal etiology of bacterial meningitis.

   Laboratory findings due to complications (e.g., Waterhouse-Friderichsen syndrome, subdural effusion)

Suggested Readings

Al Masalma M, Armougom F, Scheld WM, et al. The expansion of the microbiological spectrum of brain abscesses with use of multiple 16S ribosomal DNA sequencing.
Clin Infect Dis.
2009;48:1169–1178.

Bitnun A, Ford-Jones EL, Petric M, et al. Acute childhood encephalitis and
Mycoplasma pneumoniae
.
Clin Infect Dis.
2001;32:1674–1684.