Question

The cerebrospinal fluid (CSF) specimen of a patient is shown below along with the microscopy. The report shows mononuclear cytosis, elevated proteins, and low sugars. Which of the following is the likely etiology?

• A. Tuberculous meningitis
• B. Aseptic meningitis
• C. Bacterial meningitis
• D. Chemical meningitis

Answer 1

The Correct Option is A

The cerebrospinal fluid (CSF) analysis is crucial in diagnosing various types of meningitis. The provided CSF report indicates the following findings:

• Mononuclear cytosis: This suggests a predominance of mononuclear cells (lymphocytes) in the CSF, which is commonly associated with viral infections or tuberculosis.
• Elevated proteins: An increase in protein levels in the CSF can occur due to the breakdown of the blood-brain barrier or inflammation, as seen in conditions like tuberculous and bacterial meningitis.
• Low sugars: Hypoglycorrhachia (low CSF glucose) is especially indicative of bacterial infections, such as bacterial meningitis, or tuberculosis. The bacteria consume glucose, leading to reduced levels.

Taking into account all the CSF findings:

• **Tuberculous meningitis** is characterized by mononuclear cytosis, elevated protein levels, and low glucose levels. The presence of mononuclear cells suggests a lymphocytic predominance, typical of tuberculous rather than bacterial meningitis.
• **Aseptic meningitis** typically shows a lymphocytic predominance with normal glucose levels, which does not match the low glucose finding.
• **Bacterial meningitis** generally presents with pleocytosis, which is a predominance of neutrophils, alongside low glucose and high protein levels.
• **Chemical meningitis** can cause an inflammatory response but usually does not present with a glucose drop as marked as in infectious causes.

Considering the combination of mononuclear predominance, elevated proteins, and low glucose, the findings are most consistent with Tuberculous meningitis, making it the likely etiology given these CSF results.