A case of acute low pressure hydrocephalus (ALPH) associated with listeria meningitis

Abstract

Acute low-pressure hydrocephalus (ALPH) is a rare form of hydrocephalus that presents with decreased intracranial pressure (ICP) despite symptoms of increased ICP and ventricular enlargement. We report a case of ALPH complicated by Listeria meningitis, with a review of the literature on pathophysiology, drainage management and treatment options for ALPH. The patient is a 1-year and 10-month-old boy. He was referred to a local doctor because of fever, diarrhea, and vomiting for 5 days, and was found to have impaired consciousness and stiff neck. The cerebrospinal fluid (CSF) examination revealed elevated cell counts and low CSF glucose. However, head computed tomography (CT) showed no obvious abnormality. The patient was diagnosed with bacterial meningitis and started on antibiotic treatment. The next day, he was referred to our hospital due to status epilepticus. After admission, anisocoria was observed, and hydrocephalus was diagnosed by head CT. Consequently, emergency ventricular drainage (EVD) was performed. Intraoperative findings revealed the decompression of dura matter in burr hole and low ICP of 5 cmH₂O. Postoperatively, the patient was followed up at a pressure setting of 5 cmH₂O, but drained CSF was little and the ventricle size indicated no recovery. The protocol was changed to lower the pressure setting to promote spinal fluid drainage. The size of the ventricles gradually decreased, and the patient’s consciousness improved. On the 29th day after the operation, ventriculoperitoneal shunting (VPS) was performed and the patient was discharged home with good progress. He was followed up in the outpatient clinic, and a magnetic resonance imaging (MRI) scan of the head showed ballooning of the floor of the third ventricle. He is scheduled to undergo endoscopic third ventriculostomy (ETV) soon. ALPH is a rare condition; however, there are no clear treatment guidelines. In the literature, EVD is used as initial treatment, and VPS and ETV are used as curative treatment. In the present case, spinal fluid drainage was aggressively performed from day 10, but the duration of treatment could have been shortened by promoting drainage immediately after surgery. Although VPS was effective in this case, ETV may be considered as an initial curative treatment after EVD. In the future, ETV may be used for shunt release in the long term.