CSF examination of a patient shows high protein markedly low sugar, low chloride and increased neutrophils. The diagnosis is –
**Core Concept:** CSF examination involves analyzing cerebrospinal fluid (CSF) for cellular and biochemical parameters to diagnose central nervous system (CNS) infections, tumors, or other abnormalities.
**Why the Correct Answer is Right:**
In this question, we are looking for a diagnosis based on the provided CSF examination findings:
1. High protein indicates increased protein concentration, which may be seen in CNS infections, tumor, or inflammation.
2. Markedly low sugar suggests increased glucose utilization or impaired glucose transport across the blood-brain barrier, common in CNS infections (e.g., meningitis).
3. Low chloride is often seen in increased sodium concentration in the CSF, commonly observed in bacterial meningitis.
4. Increased neutrophils point towards a cell-mediated immune response, often seen in bacterial meningitis.
**Why Each Wrong Option is Incorrect:**
A. Low protein and normal sugar, chloride levels (hypoglycorrhachia) are more commonly seen in viral meningitis.
B. Low protein, low sugar, normal chloride, and low neutrophils are characteristic of normal pressure hydrocephalus (NPH).
C. Low protein, normal sugar, low chloride, and low neutrophils are seen in cerebral edema, which is not directly related to the abnormal findings mentioned.
D. Low protein, normal sugar, normal chloride, and normal neutrophils are indicative of ventricular catheter placement complications (CSF leak).
**Clinical Pearl:**
The correct diagnosis in this case is **A** (hypoglycorrhachia) due to the combination of high protein, low sugar, and low chloride levels, along with increased neutrophils, which are consistent with bacterial meningitis. This combination of findings helps differentiate between various types of meningitis and other CSF abnormalities.