Seronegative dementia paralytica: report of a case

Clinical significance of cerebrospinal fluid tests for neurosyphilis

From 1978 to 1987, 1,665 cerebrospinal fluid (CSF) fluorescent treponemal antibody absorption (CSF-FTA-ABS) tests were performed as the screening procedure for neurosyphilis. The CSF samples from 48 patients were reactive, and the medical history and results of the CSF-Venereal Disease Research Laboratory test (CSF-VDRL) for syphilis for 38 of these patients were reviewed. Likely active neurosyphilis was diagnosed if the patient had a reactive CSF-FTA-ABS test, recent onset of neurological signs consistent with neurosyphilis, abnormal CSF, and no other recognized cause for the neurological illness. Fifteen patients were so classified. Four had a reactive CSF-VDRL test. The specificity of the CSF-VDRL in diagnosing likely active neurosyphilis was 100%, but the sensitivity was only 27%. The insensitivity of the CSF-VDRL test limits its usefulness as a screening test for neurosyphilis. The CSF-FTA-ABS test appears more sensitive for screening but is less specific than the CSF-VDRL test in distinguishing currently active neurosyphilis from past syphilis. These findings imply that clinical judgment is still essential in establishing the diagnosis of active neurosyphilis.

A rational approach to dementia

Dementia is a common problem facing all medical practitioners and it frequently results in hospitalization and death. This review provides a framework for dealing with dementia in clinical practice that is based on both traditional concepts and recent advances in the understanding of the problem. Distinguishing at the bedside between dementia and other disorders of intellect is emphasized. The main causes of dementia and their clinical characteristics are reviewed and a rational approach to definitive diagnosis is developed. Simple, effective symptomatic forms of therapy are described.

Dementia paralytica: deterioration from communicating hydrocephalus

Five patients suffering from dementia paralytica who failed to improve or deteriorated after one or several high dosage courses of penicillin, had pneumoencephalographic patterns suggesting communicating hydrocephalus. Measurements of the ventricular index, ratio of cella media to width of the temporal horn, and the callosal angle differed from that in seven cases of dementia paralytica with associated cerebral atrophy. An isotope cisternogram in three cases with communicating hydrocephalus further confirmed a blockage of the cerebrospinal fluid (CSF) at the parasagittal subarachnoid space. Three patients exhibited the full syndrome of gait apraxia, incontinence, and pyramidal tract signs associated with a severe degree of dementia. Shunting of the CSF in three cases was followed by immediate improvement in two, one in a longlasting way. No active parenchymal inflammation was observed in any of three brain biopsy samples taken during surgery, except for leptomeningeal fibrosis in one. Chronic leptomeningitis in dementia paralytica may impair subarachnoid CSF absorption with subsequent communicating hydrocephalus. Progression or inadequate responses after therapeutic dose of penicillin in dementia paralytica should prompt investigation for this complication as an alternative, effective treatment could be offered.