What complication is diagnosed when a patient develops obstructive hydrocephalus after a shunt?

• A. Shunt malfunction
• B. Diabetes insipidus
• C. Meningitis
• D. Sepsis

Answer: (A)

When a patient develops obstructive hydrocephalus after the placement of a shunt, the most appropriate diagnosis is a shunt malfunction. This complication arises when the shunt system intended to divert cerebrospinal fluid (CSF) away from the brain fails to function correctly. A shunt can malfunction due to various reasons, such as blockage, disconnection, or improper placement, leading to an accumulation of CSF in the ventricles of the brain. This accumulation causes increased intracranial pressure and obstructive hydrocephalus.

Other potential complications, like diabetes insipidus, meningitis, or sepsis, can occur but are not directly tied to obstructive hydrocephalus caused by a shunt malfunction. Diabetes insipidus results from inappropriate secretion of antidiuretic hormone (ADH) or the kidneys' response to ADH but does not directly relate to the mechanics of CSF diversion. Meningitis is an infection that can occur after any surgical procedure involving the CNS but is separate from the issue of shunt function. Sepsis is a systemic infection that could theoretically occur in any patient but doesn’t specifically account for the obstructive hydrocephalus observed here. Therefore, identifying shunt malfunction as the primary