A child presents with fever, altered level of consciousness, and signs of meningeal irritation. Cerebrospinal fluid (CSF) analysis reveals the following findings:  • Cell differential: Predominantly lymphocytes  • Protein: Elevated  • Glucose: Low Based on these CSF findings, what is the most likely diagnosis?

1. A

   A. Tuberculous meningitis

2. B

   B. Pyogenic (bacterial) meningitis

3. C

   C. Viral meningitis

4. D

   D. Fungal meningitis

Appeared in: INI-CET EXAM -2026

Explanation

• Tuberculous (TB) meningitis is the most likely diagnosis based on the classic CSF triad presented.
• The key findings are a lymphocytic pleocytosis (predominantly lymphocytes), elevated protein concentration, and a low glucose level (hypoglycorrhachia).
• This inflammatory response is caused by Mycobacterium tuberculosis in the subarachnoid space, leading to the formation of a thick basal exudate.
• The combination of unrelenting headache, fever, and these specific CSF findings is highly suspicious for tuberculous meningitis.

Why Other Options Were Wrong

• Option B: Pyogenic (bacterial) meningitis is characterized by a predominance of neutrophils (polymorphonuclear cells) in the CSF, not lymphocytes. The cell count is also typically much higher.
• Option C: In viral meningitis, the CSF glucose level is typically normal. The question specifies low glucose.
• Option D: While fungal meningitis can present with a similar CSF profile (lymphocytic predominance, high protein, low glucose), tuberculous meningitis is a more common cause presenting with this classic triad, making it the 'most likely' diagnosis in an exam context.

Related Visual

Clinical Relevance

• Nursing practice connection: Use the key finding related to Interpretation of Cerebrospinal Fluid (CSF) analysis for diagnosing different types of meningitis to guide bedside assessment, documentation, and the next nursing action.
• Rapid and accurate interpretation of CSF findings is a critical nursing skill to facilitate timely and appropriate treatment, which significantly impacts patient outcomes in meningitis.
• Tuberculous meningitis requires a long course of specific multi-drug anti-tubercular therapy, which is vastly different from the antibiotics for bacterial meningitis or supportive care for viral meningitis.
• Nurses must monitor for signs of increased intracranial pressure (ICP), such as changes in consciousness, pupillary changes, and Cushing's triad, which is a common complication of meningitis.

How to Approach the Question

• First, identify the key clinical information provided: a child with signs of meningitis (fever, altered consciousness, meningeal irritation).
• Next, focus on the laboratory data, which are the CSF results. Break them down into the three main components: cell type, protein level, and glucose level.
• Systematically compare the given CSF profile (lymphocytes, high protein, low glucose) with the known classic profiles for each type of meningitis listed in the options.
• Recall or deduce that neutrophil predominance points to bacterial meningitis.
• Recall or deduce that normal glucose points to viral meningitis.
• Recognize that the combination of lymphocytes, high protein, and low glucose is the classic presentation for tuberculous meningitis.

Concept Tested & Keywords

• Concept Tested: Interpretation of Cerebrospinal Fluid (CSF) analysis for diagnosing different types of meningitis.
• Stem keywords: fever, altered level of consciousness, meningeal irritation, Cerebrospinal fluid (CSF) analysis, lymphocytes, elevated protein, low glucose
• Lead-in keywords: most likely diagnosis
• Clinical cues: The combination of lymphocytic predominance, high protein, and low glucose in CSF is a classic triad pointing towards a specific etiology.

Question ID

QsQxEiqgmA3t7kBmh0Pjc1

Copy ID

Reference Book

E6 Medicine Harrison 22e Part 1 pp. 1168-1170, 1165-1167

E6 Ghai Essential Pediatrics(pp 26-904 of 913) p. 586-588