A 25-year-old college student presents with progressive headache, vomiting, and double vision. Examination reveals bilateral 6th nerve palsy and papilledema. CT brain shows hydrocephalus. CSF analysis reveals lymphocytic dominance, markedly low glucose, and elevated protein. What is the most likely diagnosis?

1. A

   A. Viral meningitis

2. B

   B. Tubercular meningitis

3. C

   C. Fungal meningitis

4. D

   D. Bacterial meningitis

Appeared in: INI-CET EXAM -2026

Explanation

• The patient's clinical triad of subacute neurological symptoms (progressive headache, vomiting), signs of increased intracranial pressure (papilledema), and focal deficits (6th nerve palsy) is characteristic of Tubercular (TB) Meningitis.
• The key diagnostic clue is the cerebrospinal fluid (CSF) profile: a predominance of lymphocytes, markedly low glucose levels, and elevated protein.
• TB meningitis typically causes a thick inflammatory exudate at the base of the brain, which explains both the hydrocephalus (by blocking CSF pathways) and the cranial nerve palsies (by encasing the nerves).
• The 6th cranial nerve is commonly affected in TB meningitis due to its long intracranial course, making it susceptible to stretching and compression from increased intracranial pressure.

Why Other Options Were Wrong

• Option A: In viral meningitis, the CSF glucose level is typically normal or only slightly decreased. The patient's markedly low glucose makes this diagnosis highly unlikely.
• Option C: Fungal meningitis can present with very similar CSF findings to TB meningitis (lymphocytic pleocytosis, low glucose). However, TB is a more common cause of this classic presentation, especially the prominent basal meningitis signs like cranial nerve palsies and hydrocephalus. Fungal meningitis is also more frequently seen in immunocompromised patients.
• Option D: Acute bacterial meningitis is characterized by a predominance of neutrophils (polymorphonuclear cells) in the CSF, not lymphocytes. Also, the clinical onset is typically hyperacute (developing over hours), not progressive.

Related Visual

Clinical Relevance

• Nursing practice connection: Use the key finding related to Differential diagnosis of meningitis based on clinical presentation and cerebrospinal fluid (CSF) analysis to guide bedside assessment, documentation, and the next nursing action.
• Early diagnosis and initiation of multi-drug anti-tubercular therapy (ATT) are critical in TB meningitis to prevent severe, permanent neurological disability or death.
• Nurses play a vital role in managing patients with TB meningitis by meticulously monitoring neurological status (Glasgow Coma Scale, pupillary response, cranial nerve function), managing symptoms of increased intracranial pressure, and ensuring strict adherence to the complex, long-term medication regimen.
• What if? If the CSF had shown a predominance of neutrophils instead of lymphocytes, the immediate priority would shift to suspecting acute bacterial meningitis, and empiric broad-spectrum antibiotics would be started immediately, even before culture results are back.

How to Approach the Question

• First, analyze the patient's clinical presentation. Note the subacute (progressive) nature of the symptoms and the specific neurological signs: 6th nerve palsy (cranial nerve deficit) and papilledema (sign of increased intracranial pressure).
• Next, examine the imaging finding: hydrocephalus. Connect this to the signs of increased intracranial pressure.
• The most critical step is to interpret the CSF results. Break it down into three key components: cell type (lymphocytic), glucose level (markedly low), and protein level (elevated).
• Systematically compare this CSF profile with the classic patterns for each option. Rule out bacterial meningitis due to the lymphocytic (not neutrophilic) predominance. Rule out viral meningitis due to the markedly low (not normal) glucose.
• Differentiate between tubercular and fungal meningitis. The combination of basal meningitis signs (hydrocephalus, cranial nerve palsy) with this CSF profile makes TB meningitis the most classic and likely diagnosis.

Concept Tested & Keywords

• Concept Tested: Differential diagnosis of meningitis based on clinical presentation and cerebrospinal fluid (CSF) analysis.
• Stem keywords: progressive headache, vomiting, double vision, bilateral 6th nerve palsy, papilledema, hydrocephalus, CSF analysis, lymphocytic dominance
• Lead-in keywords: most likely diagnosis
• Clinical cues: The combination of subacute onset, cranial nerve palsy (6th nerve), and hydrocephalus points towards a process at the base of the brain, classic for TB meningitis.
• Clinical cues: Markedly low CSF glucose with lymphocytic predominance is a key feature that strongly differentiates TB and fungal meningitis from viral meningitis.

Question ID

QpfwuY5ltNaVT_cEzyj51W

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Reference Book

E6 PATHOLOGY QUICK REVIEWBased on Harsh Mohan Textbook of PATHOLOGY p. 265-267

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 1565-1567