Khalil Ullah

OBJECTIVE: To describe our experience of post-transplant infections in allogeneic stem cell transplants at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan. METHODS: From July 2001 to September 2006, patients with malignant and non-malignant hematological disorders having human leukocyte antigen (HLA)-matched sibling donors were selected for transplant. Pre-transplant infection surveillance was carried out, and strict prophylaxis against infection was observed. After admission to the hospital, patients were kept in protective isolation rooms, equipped with a HEPA filter positive-pressure laminar airflow ventilation system. Bone marrow and/or peripheral blood stem cells were used as the stem cell source. Cyclosporin and prednisolone were used as prophylaxis against graft-versus-host disease (GVHD). The engraftment was monitored with cytogenetic/molecular analysis and change of blood group. Survival was calculated from the date of transplant to death or last follow-up. RESULTS: One hundred and fifty-four patients received allogeneic stem cell transplants from HLA-matched siblings for various hematological disorders at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan between July 2001 and September 2006. Indications for transplant included aplastic anemia (n=66), beta-thalassemia major (n=40), chronic myeloid leukemia (n=33), acute leukemia (n=8), and miscellaneous disorders (n=7). One hundred and twenty patients were male and 34 were female. The median age of the patient cohort was 14 years (range 1 1/4-54 years). One hundred and thirty-six patients and 135 donors were cytomegalovirus (CMV) IgG-positive. One hundred and forty patients (90.9%) developed febrile episodes in different phases of post-transplant recovery. Infective organisms were isolated in 150 microbiological culture specimens out of 651 specimens from different sites of infections (23.0% culture positivity). Post-transplant infections were confirmed in 120 patients (77.9%) on the basis of clinical assessment and microbiological, virological, and histopathological examination. Mortality related to infections was 13.0%. Fatal infections included CMV disease (100% mortality, 6/6), disseminated aspergillosis (66.7% mortality, 4/6), pseudomonas septicemia (42.9% mortality, 9/21), and tuberculosis (25% mortality, 1/4). CONCLUSIONS: More than 90% of our patients developed febrile episodes with relatively low culture yield. The majority of infections were treated effectively, however CMV, aspergillosis, and pseudomonas infections remained problematic with high mortality.

OBJECTIVE: To evaluate the role of isoniazid prophylaxis in prevention of tuberculosis among allogeneic stem cell transplant recipients. METHODS: This study was conducted at Armed Forces Bone Marrow Transplant Center Rawalpindi, Pakistan from July 2001 to October 2003. Patients suffering from various haematological disorders undergoing allogeneic stem cell transplantation were included in the study. The demographic information, primary diagnoses and relevant investigations were recorded. Patients had negative tuberculin skin tests and chest X-Ray at pre-transplant assessment. First 25 patients (group I) did not receive isoniazid prophylaxis while the next 25 (group II) were given isoniazid in a dose of 5-10 mg/kg (maximum 300 mg/day). Isoniazid prophylaxis was started on day-1 and continued for 6 months post transplant. The patients developing tuberculosis were treated with rifampicin, ethambutol, isoniazid, and pyrazinamide during first 3 months followed by 2 drugs for a total duration of 12 months. Minimum follow up in group I and II was 783 and 403 days respectively. RESULTS: There was significant difference (p < 0.001) in frequency of tuberculosis between two groups. In group I, four patients developed Tuberculosis (frequency 16%) whereas none of the patients in group II had the disease. Out of these four cases 3 had extrapulmonary disease. One patient died two weeks after the start of anti tuberculosis treatment while others successfully completed the treatment. CONCLUSION: Tuberculosis in stem cell transplant recipients is an important opportunistic infection especially in areas of high disease prevalence like Pakistan. Isoniazid prophylaxis for 6 months is effective in preventing tuberculosis among this class of patients.

OBJECTIVE: To assess magnitude of tuberculosis (TB) in patients suffering from various haematological malignancies and stem cell transplant (SCT) recipients. DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Oncology Department, Combined Military Hospital, Rawalpindi, and Armed Forces Bone Marrow Transplant Centre, Rawalpindi, from July 2001 to December 2002. PATIENTS AND METHODS: Patients suffering from various haematological malignancies treated between July 2001 and December 2002 were included in the study. The hospital records and out-patient follow-up charts were reviewed for demographic information, diagnosis, clinical presentation, laboratory investigations, radiological and pathological examinations, sites involved in TB, methods of diagnosis, number and type of anti-tuberculosis drugs given and response to treatment. RESULTS: During the study period a total of 213 (including 25 allogeneic stem cell transplant (SCT) recipients) patients with different haematological disorders were treated. Out of these, 34, including 4 SCT recipients developed tuberculosis. Overall frequency of TB was 16 %. Median age of TB patients was 33.5 years (range 8-80 years). Median time between diagnosis of haematological disorders and tuberculosis was 21 weeks. Sites of involvement by TB were lung (18), disseminated (6), lymph node (5), pleura (2), spine (2) and pericardium (1). Three of the patients died of TB; one undiagnosed, second with multi-drug resistant TB and the third soon after the start of anti-tuberculosis treatment while remaining 31 cases responded to anti-tuberculosis treatment. CONCLUSION: Tuberculosis is a major problem in immunocompromised patients and there is need to establish guidelines for TB chemoprophylaxis in our setup.

Electroencephalogram (EEG) is a medical imaging technology that can measure the electrical activity of the scalp produced by the brain, measured and recorded chronologically the surface of the scalp from the brain. The recorded signals from the brain are rich with useful information. The inference of this useful information is a challenging task. This paper aims to process the EEG signals for the recognition of human emotions specifically happiness, anger, fear, sadness, and surprise in response to audiovisual stimuli. The EEG signals are recorded by placing neurosky mindwave headset on the subject’s scalp, in response to audiovisual stimuli for the mentioned emotions. Using a bandpass filter with a bandwidth of 1–100 Hz, recorded raw EEG signals are preprocessed. The preprocessed signals then further analyzed and twelve selected features in different domains are extracted. The Random forest (RF) and multilayer perceptron (MLP) algorithms are then used for the classification of the emotions through extracted features. The proposed audiovisual stimuli based EEG emotion classification system shows an average classification accuracy of 80% and 88% using MLP and RF classifiers respectively on hybrid features for experimental signals of different subjects. The proposed model outperforms in terms of cost and accuracy.