Beta-2-microglobulin in the cerebrospinal fluid of patients with infections of the central nervous system.

Beta-2-microglobulin was determined in 147 patients admitted to hospital because of suspicion of CNS disease. Patients with meningism were chosen as control group. The concentration of beta-2-microglobulin in the spinal fluid of control patients was correlated with age. Reference values for 0-40 years were 0.34-1.58 mg/l. Above 40 years of age the values were 0.46-3.14 mg/l. CSF beta-2-microglobulin levels of patients with meningism, aseptic and bacterial meningitis overlap too much to be relevant in distinguishing between these entities. Five patients with herpes simplex encephalitis had markedly elevated levels ranging from 4.4 to 9.0 mg/l. Ten patients with herpes zoster-associated encephalitis had values from 1.1 to 6.1 mg/l. In the patient groups with CNS infections, the ratio of serum to spinal fluid beta-2-microglobulin was significantly more frequently less than 1 as compared with the meningism group, indicating intrathecal production of the protein. Further studies on the clinical relevance of CSF beta-2-microglobulin in the diagnosis of encephalitis seem warranted.

Open study of 2-amino-9-(hydroxyethoxymethyl)-9H-purine (desciclovir) in the treatment of herpes zoster.

An oral pro-drug of acyclovir, 2-amino-9-(2-hydroxyethoxymethyl)-9H-purine (desciclovir) was evaluated in an open study comprising of 20 patients with herpes zoster. The clinical effects were comparable to those obtained with oral and intravenous acyclovir, even with a dosage of only 125 mg thrice daily. There was adequate absorption though considerable individual variation occurred. No effects of concomitant food intake were demonstrated. The finding of possible impaired conversion of desciclovir to acyclovir in one patient was unexplained and deserves attention in future studies. Likewise, more studies are needed to understand the occurrence of transient high peak plasma concentrations of acyclovir. Side-effects other than those already known with the use of acyclovir, namely reversible tubular damage, were not observed.

Prednisolone does not prevent post-herpetic neuralgia.

In a randomised, double-blind, controlled study of the effect of prednisolone on the development of post-herpetic neuralgia 78 patients with herpes zoster whose pain and exanthema had been present for less than 96 h were given 800 mg acyclovir five times daily for 7 days and prednisolone in a total dose of 575 mg, starting with 40 mg daily in the first week and tapering off over the next 2 weeks. 18 (23%) of the patients had post-herpetic neuralgia at 6 months after the acute zoster, 9 (24.3%) having received prednisolone and 9 (22.5%) placebo. The 95% CI for the difference between the placebo and prednisolone groups in the proportion of patients having pain at 6 months was minus 17% to plus 20%. Prednisolone, however, relieved pain for the first 3 days. The 1-2 week interval between admission and reappearance of pain and development of triggered pain seems to be the time needed to establish neuralgia. Once established, the type and intensity of pain remained largely unaltered.