Simultaneous serum and CSF antibodies in herpes simplex virus encephalitis

Area of Science:

• Neurology
• Virology
• Immunology

Background:

• Herpes simplex virus encephalitis (HSVE) is a severe neurological condition.
• Accurate and timely diagnosis of HSVE is crucial for effective treatment and patient outcomes.

Purpose of the Study:

• To evaluate the diagnostic utility of serum/cerebrospinal fluid (S/CSF) antibody titers in patients with HSVE.
• To determine if specific S/CSF antibody titer ratios can reliably differentiate HSVE from other neurological conditions.

Main Methods:

• Serial serum (S) and cerebrospinal fluid (CSF) samples were collected from eight patients with biopsy-proven HSVE and 28 controls.
• Antibody titers were measured using passive hemagglutinating (PHA) and immune adherence hemagglutinating (IAHA) tests, before and after 2-mercaptoethanol reduction.
• The ratio of S/CSF antibody titers was calculated and analyzed.

Main Results:

• A S/CSF antibody titer ratio ≤ 20 was observed in all HSVE patients, both before and after 2-mercaptoethanol reduction.
• This ratio was diagnostic for HSVE in some patients before brain biopsy and within ten days of symptom onset.
• Control subjects predominantly exhibited S/CSF ratios > 20, with exceptions having distinct neurological diagnoses.

Conclusions:

• The S/CSF antibody titer ratio, particularly using PHA or IAHA tests, provides a rapid and reliable method for diagnosing HSVE.
• This diagnostic approach can aid in early identification of HSVE, potentially improving patient management.