Tuberculosis affecting the nervous system: can we trace the source of infection?

ABSTRACT

To trace the source of tuberculous infection of patients with CNS tuberculosis. We analyzed clinical records of 100 patients with tuberculosis affecting the central nervous system, who presented to Department of Neurology Civil Hospital Karachi,between Jan 2007 To June 2010. All patients with confirmed diagnosis of CNS tuberculosis, supported by clinical, laboratory, and radiological evidence were included. Case histories were analyzed and notes were made in each case of past history of tuberculosis, history of affected family members at that time and in past, and presence or absence of concurrent extra-neural tuberculosis. All patients with disseminated tuberculosis were investigated for immunocompromised states like HIV. Patients with positive contact history were divided into those with tuberculosis affected person within their household, those with their first degree relatives with history of tuberculosis, and those with workmates or other regular contacts with tuberculosis. Contacts of all these patients were also investigated to find out the new cases amongst them according to the WHO guidelines. Results were analyzed on SPSS. Among the total of 100 patients, male to female ratio was 13 with ages ranging from 8 to 82 years. Mean age was 34. Fifty six people had tuberculosis affecting brain and 44 had spinal involvement. Thirty five patients had tuberculous meningitis, 13 had tuberculous meningitis with tuberculomas, and 8 had tuberculomas only. Major complications of tuberculous meningitis, like stroke [60%], hydrocephalus [40%] and optic neuropathy [1.5%] were seen in 20 patients. One patient had sagittal sinus thrombosis in addition to tuberculous meningitis. 44 patients had spinal cord involvement, they presents with compressive myelopathy, [tuberculous abscess and/or prolapsed vertebrae] and/or myelitis. Twelve patients showed involvement of cervical spine, 16 dorsal spine and 15 had lumbar spine involvement. One patient had disease of dorsolumbar spine. Neurosurgical procedures were required in those who developed hydrocephalous and epidural spinal cord abcesses. At the time of presentation, 20 patients had tuberculous infection in extra-neural tissues /organs as well. Four patients had abdominal tuberculosis, 6 had disseminated tuberculosis, and 10 had pulmonary tuberculosis. Baseline chest xray was abnormal in 20% of patients [10% with active concurrent pulmonary tuberculosis while other 10% were asymptomatic. Fourteen patients had history of tuberculosis in past. Six had pulmonary tuberculosis in past but x-ray evidence of tuberculosis was available in other two, 2 were diagnosed with abdominal tuberculosis, 3 had tuberculous lymph adenitis, and one patient was diagnosed as tuberculous meningitis. Twenty six percent of patients could trace the source of infection among their relatives, while majority [74%] did not give history of any affected family member, relative or contact, at that time or in past. Fourteen percent had an affected household [parent, sibling], and 12% gave history of an affected first degree relative. Tracing the source of infection with clinical methods alone was not very much beneficial. We need advance strategies to supplement our clinical methods to find out the source of transmission of this illness and to eradicate and manage effectively the spread of infection in our community