Chronic meningitis in Thailand. Clinical characteristics, laboratory data and outcome in patients with specific reference to tuberculosis and cryptococcosis.

The charts of 114 consecutive patients with chronic meningitis admitted to a general hospital in Bangkok, Thailand, between 1993 and 1999 were retrospectively reviewed. The most common causative agents were Cryptococcus neoformans (54%) and Mycobacterium tuberculosis (37%). HIV and other underlying diseases had a major impact on the presentation of chronic cryptococcal meningitis patients. Compared to HIV-negative cryptococcal meningitis patients (21%), HIV-positives (79%) had a significantly lower incidence of focal signs (p = 0.02), hydrocephalus (p = 0.03) and seizures (p = 0.001) during hospital stay, furthermore, a lower leucocyte level, a significantly higher glucose level (p = 0.02) and a lower protein level (p = 0.03) in the first cerebrospinal fluid examination. Of the 43 patients with chronic tuberculous meningitis, only 3 were HIV positive. Focal neurologic deficits were found more frequently in tuberculous meningitis patients (p = 0.001) when compared to cryptococcal meningitis patients without HIV. Cerebral infarction on cerebral CT was indicative of tuberculous meningitis. Cryptococcal meningitis patients with HIV infection had a worse outcome compared to non-AIDS patients. Advanced stage of the disease on admission, decreased level of consciousness prior to and on the admission day and raised intracranial pressure above 40 cm H(2)O at any given time were predictive of a poor outcome in tuberculous meningitis patients.

Long-term follow-up of myasthenia gravis patients with hyperthyroidism.

OBJECTIVE: To access clinical characteristics and treatment outcome of myasthenia gravis (MG) patients with hyperthyroidism (HT). MATERIALS AND METHODS: The clinical characteristics of 51 MG patients with HT were studied. The treatment outcome was analysed in 34 patients, comparing high-dosage prednisolone (HDP) (group IS), HDP and/or immunosuppressants with antithyroid drugs (group IS + antiHThyr), antithyroid drugs (group antiHThyr), and thymectomy. RESULTS: The prevalence of HT in MG was 17.5%. Group IS showed higher remission of both diseases compared with group antiHThyr, but not with group IS + antiHThyr. Remission of HT and relapse of both diseases showed no difference among the three groups. Ten patients who had thymectomies had a lower relapse of MG but not of HT, whilst remission of both diseases was no different to 24 non-thymectomy patients. CONCLUSION: This study showed a high prevalence of HT in Thai MG. HDP alone can induce remission of both diseases without difference in relapse. Thymectomy lowers MG relapse further but has no influence on HT.

Clinical features and clinical course of multiple sclerosis in Thai patients: a report of 50 cases.

During a twenty-year period 1967-1986, clinical features and clinical course of 50 patients with proved (in 3), clinically definite (in 32), early probable (in 13) and suspected (in 2) cases of multiple sclerosis were studied. Certain clinical characteristics in Thai patients are noteworthy, namely, a higher female to male ratio (4:1), a higher rate of optic nerve involvement (76%), and lower rate of brain stem involvement (30%) and cerebellar involvement (10%) during the course of illness in contrast to those of Western series. Painful tonic seizure was a prominent feature in Thai patients with multiple sclerosis (22/50 or 44%). Thirty out of 50 patients could be traced. Ten patients had died (33%) from the disease after 1-21 years with a mean of 8.08 years. Twenty patients (66%) were still alive. The follow-up period was 2-12 years with an average of 6.65 years. Among the twenty, 3 were bed-ridden, 3 were chair-bound and 5 had restricted activities. Nine patients (30%) were still working fully.

The practice of neurology in Thailand. A different type of medical specialist.

A survey of 1700 patient encounters during 1 week of practice by 23 neurologists in Thailand delineates a different scope of specialty practice compared with that of many Western nations. Thai neurologists had an average of 96 patient encounters per week of practice, with two thirds of all encounters in ambulatory care. However, one half of all encounters were for self-referred patients, three fourths of all encounters were regular patients for whom the neurologist provided continuing care, and about one half of all encounters were thought to reflect health problems that fall within the scope of general internal medicine. The data suggest that Thai neurologists function in health care delivery as general internists with special competencies and interests in the field of neurology. This balanced style of specialist practice serves to reinforce the primary care infrastructure of the health system in developing countries.

Is cryptococcal meningoencephalitis in the tropics a distinct entity? A retrospective study from Thailand.

Twenty-four consecutive patients with central nervous system cryptococcosis (C.C.) have been studied retrospectively. In contrary to many reports from America or Europe only two patients suffered from an underlying immunocompromising disease. All patients were treated uniformly by amphotericin B and 5-fluorocytosin. They were monitored closely and dose-adjustment was done according to laboratory data. None of the patients died. Sixteen were available for a six-month post-treatment follow-up: seven had various degrees of neurological long-term sequelae whereas nine had no complaints and neurological examination was without abnormal findings. Our series is compared with others both from tropical and non-tropical countries. In accordance with all but one larger series from the tropics the relatively good prognosis and extremely rare occurrence of C.C. in immunocompromised persons is noted. Since different varieties of Cryptococcus neoformans have been shown to exist in different climate zones, this might be one of the possible explanations for the lack of preceding immune-compromising conditions in persons suffering from C.C. in the tropics and the benign course of disease.

Regional curare test in the study of neuromuscular transmission in hyperthyroidism.

The findings in this study suggest that there is defect in the neuromuscular transmission in hyperthyroidism. This abnormality was detected in 62 per cent of the patients and did not directly correlate with proximal muscle weakness present in most of the patients. It seems that the weakness in hyperthyroidism is the result of myopathy as well as neuromuscular transmission both of which might be due to the same metabolic derangement but are not directly related. After treatment, the muscle power became normal in all of the patients and the neuromuscular transmission was normalized in most but not all of them. It is possible that this transmission defect may be due to other mechanisms apart from the hormonal disorder e.g. the same processes as that which occurs in myasthenia gravis. The underlying pathophysiology is worth further exploration.

Rapid diagnosis of rabies and post-vaccinal encephalitides.

In an attempt to establish the diagnoses of rabies post-vaccinal encephalitis (PVE) and early rabies encephalitis, paired serum and CSF levels of rabies neutralizing antibody (Rab) and rabies specific-IgM (RIgM) were compared in 12 PVE, 10 rabies and five control patients with similar presenting clinical features. Rapid methods of rabies antigen detection were evaluated in 17 patients. All 12 PVE patients had Rab in their serum and in eight it was also present in the CSF. These same eight had RIgM in the serum, and in seven also in the CSF. The CSF antibodies may have originated in the plasma since six patients had a high albumin quotient indicating leakage across the blood-brain barrier. Among the rabies patients, only the two vaccinated ones had serum Rab; this was also detected in the CSF of one and RIgM was in the CSF of the other. A raised IgG Index, indicating intrathecal synthesis of IgG was seen in five of 12 PVE patients. This did not correlate with the presence of CSF rabies antibody, suggesting production of antibody to other vaccine antigens of neural origin. The diagnosis of rabies encephalitis in life was made by antigen detection in a skin biopsy. No false positive results occurred and the method was as efficient as immunofluorescence of a post-mortem brain biopsy.

Eosinophilic meningitis and radiculomyelitis in Thailand, caused by CNS invasion of Gnathostoma spinigerum and Angiostrongylus cantonensis.

During the 6 year period from January 1980 to December 1985 44 patients with infection of the central nervous system by Gnathostoma spinigerum or Angiostrongylus cantonensis were admitted to the Division of Neurology, Ramathibodi Hospital, Bangkok, Thailand. In 16 patients the diagnosis could be confirmed serologically by means of ELISA techniques. In gnathostomiasis encephalitis, myelitis, radiculitis and subarachnoid haemorrhage formed the majority of clinical syndromes. Intracerebral haematoma and transitory obstructive hydrocephalus are described in this report as being caused by Gnathostoma spinigerum infection for the first time. In angiostronglyus infections the clinical syndrome of meningitis was predominant, but one patient, whose angiostrongyliasis was proved serologically, also showed bilateral paresis of abducens nerve. The main laboratory finding was eosinophilic pleocytosis in the CSF (greater than 10%) which in patients originating or returning from South-East-Asia, particularly Thailand, is highly suggestive of these parasitic infections. Increasing transcontinental travel, influx of refugees and those seeking asylum as well as importation of food from South East Asian countries demand greater awareness of these parasitic infections even in Central Europe.

Treatment of tuberculous meningitis: role of short-course chemotherapy.

Twenty-eight adult patients admitted consecutively with tuberculous meningitis were treated with pyrazinamide, isoniazid, rifampicin and streptomycin daily during the first two months, followed by isoniazid and rifampicin daily for seven months with intensive management of the complications during the active stage of the meningitis. Twenty-two patients completed the course of treatment and recovered with minimal morbidity in three patients. Two patients died in a vegetative state from other causes seven and nine months after the start of treatment. No evidence of recurrence of meningitis was observed in the 21 patients who were regularly observed for 12 to 29 months after completing treatment. Four patients dropped out during the early stage of treatment. Intensive chemotherapy of tuberculous meningitis with this regimen before the development of serious neurological damage can shorten the duration of treatment to nine months with a favourable outcome.

Penicillin concentrations in cerebrospinal fluid after different treatment regimens for syphilis.

The concentrations of penicillin in the cerebrospinal fluid (CSF) were compared simultaneously with those in the serum in 17 patients with syphilis. The antibiotic concentrations were measured by the agar well diffusion method. There were no detectable concentrations of penicillin in the CSF after administration of benzathine penicillin 2.4 megaunits, benzathine penicillin 7.2 megaunits, procaine penicillin in aluminium monostearate (PAM) 12 megaunits, or aqueous procaine penicillin G 2.4 megaunits. Only after high doses of aqueous penicillin G 24 megaunits daily or aqueous penicillin G 2 megaunits daily together with oral probenecid 2 g daily was penicillin detectable in the CSF. The concentrations after the latter regimen were the highest and much higher than the minimum inhibitory concentration for Treponema pallidum.

Electrophysiologic findings and prognosis in Bell's palsy.

Electrophysiologic investigations were carried out on 45 patients with Bell's palsy at periodic intervals after the onset of paralysis. It was found that there was a good correlation between prognosis in Bell's palsy and the amplitude of evoked motor response obtained after six or more days of clinical paresis. When the average amplitude of evoked motor response was within normal limits (i.e., 504 mu V or greater), complete recovery with no residual deficits took place two to six weeks after the onset of facial palsy. When the evoked motor response was absent in all three major branches of the facial nerve, indicating complete nerve degeneration, electromyographic signs of recovery were apparent by the third of fourth month after the onset of paralysis. In these cases, recovery was relatively slow and incomplete, with some degree of residual deficit and synkinesis. Maximal return of voluntary facial movement was established 8 to 12 months after the initial symptom. When the mean amplitude of evoked motor response was below the lower limit of normal (i.e., less than 504 mu V), electromyographic signs of recovery were noted within 1 to 3 months, depending on the amplitude values. The final outcome of this intermediate group was similar, but not identical, to that of the previous group. The prognosis of facial paralysis in Bell's palsy was thus found to be directly related to the mean amplitude of evoked motor response, regardless of the extent of clinical paralysis.

Parasitic diseases of the nervous system in Thailand.

In Thailand there are 3 parasites that commonly cause neurological diseases in man. 1) In gnathostomiasis man becomes an accidental host by eating infected under-cooked fresh water fish. The tissue nematode involved, Gnathostoma spinigerum, because of its high motility, may cause widespread damage in the spinal cord and brain stem. The common presenting neurological symptoms are severe nerve root pain, paralysis of limbs and urinary retention. Less frequently seen are cranial nerve palsies and symptoms of subarachnoid haemorrhage. The disease has significant morbidity and mortality. 2) Eosinophilic meningitis caused by Angiostrongylus cantonensis, the lungworm of rats, has a more benign, self limiting course. It occurs in Thai people of lower socio-economic groups who acquire the parasite by eating infected raw Pila snails. 3) Cysticercus cellulosae, caused by Taenia solium, commonly results in epilepsy, and sometimes increased intracranial pressure from intraventricular obstruction or from basal arachnoiditis. Spinal cord and cauda equina involvement occurs much less frequently. Cysticercus complement fixation tests on the CSF and computerised axial tomography have been found to be of great diagnostic value.