E.A.H. Hische

Intrathecal synthesis of antibodies to HTLV-III in patients without AIDS or AIDS related complex.

De novo synthesis in the central nervous system of IgG antibodies to human T cell lymphotropic virus type III (HTLV-III) (lymphadenopathy associated virus) was shown in seven of 10 seropositive men who had syphilis but not the acquired immune deficiency syndrome (AIDS) or AIDS related complex. None of these men showed neurological symptoms when the serum and cerebrospinal fluid were collected. Pleocytosis was present in all 10. Of the seven men who showed evidence of intrathecal synthesis of antibodies, five had increased total concentrations of IgG and four had oligoclonal IgG bands in their cerebrospinal fluid. Oligoclonal bands were also present in one man who did not have any antibodies. Longitudinal study of one man showed that seroconversion preceded intrathecal synthesis of antibody specific to HTLV-III. The appearance of antibody in the cerebrospinal fluid was accompanied by a transient rise in mononuclear cell count and the appearance of oligoclonal bands. The presence of clones of B cells specific to HTLV-III in the central nervous system of these patients without persisting neurological symptoms suggests that HTLV-III enters the central nervous system in the early stages of infection.

Effect of early and late syphilis on central nervous system: cerebrospinal fluid changes and neurological deficit.

Neurological examination and investigation of the cerebrospinal fluid (CSF) was performed on 24 patients with early and 180 patients with late syphilis. In 21 (12%) patients with late syphilis positive CSF treponemal test results and neurological deficits suggestive of symptomatic neurosyphilis were found. Concomitantly all but three patients with neurosyphilis showed one or more of the following abnormal CSF variables: CSF concentration of albumin X 10(3)/serum concentration (albumin ratio) greater than or equal to 7.9; mononuclear cells greater than 5 microliters: ratio of CSF to serum IgG concentrations/ratio of CSF to serum albumin concentrations (IgG index) greater than or equal to 0.7 or of IgM/albumin (IgM index) greater than or equal to 0.1; or oligoclonal CSF immunoglobulins. In 20 (95%) patients with neurosyphilis evidence of the production of treponemal antibodies within the central nervous system (CNS) was shown. Ten (48%) patients with neurosyphilis had been treated previously for late syphilis. These observations emphasise the need to screen for neurosyphilis in patients with late syphilis. Intrathecal production of treponemal antibodies was detected in six (25%) patients with early and 44 (28%) with late syphilis who did not show any neurological deficit. Intrathecal production of treponemal antibodies indicating that the CNS was affected led us to suspect asymptomatic neurosyphilis in these patients. Seventeen (11%) patients with late syphilis but no neurosyphilis and only one (4%) with early syphilis showed additional abnormal CSF variables. Surprisingly, six out of 22 patients with treated early and 20 out of 68 patients with treated late syphilis showed evidence of treponema antibody production within the CNS. We do not know whether these findings indicate that the CNS was affected because of inadequate treatment or merely reflect persistent synthesis of treponemal antibodies associated with cured infection. In one (4%) patient with early and in 21 (13%) with late syphilis but no neurosyphilis abnormal CSF variables in the absence of positive CSF treponemal test results were observed, which excluded syphilitic inflammation of the CNS.

The significance of the estimation of serum myoglobin in neuromuscular diseases

The serum myoglobin concentration was determined and compared with the serum creatine kinase activity in 230 patients suffering from various neuromuscular diseases. No correlation was found between the two levels. In general serum creatine kinase activity estimation seemed more sensitive for the detection of neuromuscular disease than serum myoglobin estimation. In myotonic dystrophy, however, determination of serum myoglobin was distinctly the more sensitive method.

Comparison of the spectrophotometric determination and the two-stage coagulation assay of tissue factor activity

The tissue factor activity of human brain thromboplastin and 6 commercial thromboplastins was determined by a spectrophotometric method and a two-stage coagulation assay. The thromboplastins were incubated with an excess of Factor VII and Factor X, and the activation of Factor X was estimated from the rate of hydrolysis of the chromogenic substrate S-2222 and from the coagulation time of plasma enriched in phospholipids. The results obtained by the two methods were related linearly and showed a correlation coefficient of 0.89. The coefficient of variation was 11% in the spectrophotometric method and 25% in the two-stage coagulation assay.

An improved method for the concentration of cerebrospinal fluid cells by suction tip and sedimentation chamber

To concentrate cells from cerebrospinal fluid, a new method was developed. The technique is a modification of the cell sedimentation method of Sayk. The fluid is absorbed after passing through a Nuclepore filter, pore size 0.4 micron. With the aid of simple utensils it is possible to obtain a cell preparation of high quality using only 0.3 ml of cerebrospinal fluid. The cytomorphology is as good as that achieved by Sayks sedimentation technique. The cell yield was determined using an accurate and precise method to estimate the number of cells present in the cerebrospinal fluid. The average cell yield is 90%, and all staining methods are applicable. The system is easily modified, and can be suited to many other fluids and purposes.

Immunoglobulin D in cerebrospinal fluid

Immunoglobulin D (IgD) was measured by radioimmunoassay in paired cerebrospinal fluid and serum samples from patients with various neurological diseases. The IgD index was calculated for every patient and compared with the IgG index. An increased IgD index was found in 18 out of 41 patients suffering from multiple sclerosis and in 52 out of all 122 patients investigated. An increased IgD index did not always coincide with an increased IgG index. An increased IgD index suggests an abnormal intrathecal synthesis of this immunoglobulin within the central nervous system. We conclude that the determination of IgD in the cerebrospinal fluid yields additional information on immunological reactions within the central nervous system.

The IgG index and the diagnosis of MS: a Bayesian approach

Having determined immunoglobulin G (IgG) and albumin concentrations in 1100 cerebrospinal fluid and serum samples, we calculated the IgG index. Likelihood ratios for MS were calculated by using a training set consisting of 100 patients with definite MS, and one consisting of 97 patients suffering from diseases from which MS must be differentiated.