Single voxel magnetic resonance spectroscopy in distinguishing focal neoplastic from non-neoplatic brain lesions

Objective: Assess diagnostic utility of combined magnetic resonance imaging and magnetic resonance spectroscopy (MRI, MRS) in differentiating focal neoplastic lesions from focal non- neoplastic (infective or degenerative) brain lesions.Design: Descriptive, analytical - prospective study.Setting: The Aga Khan University MRI department.Subject: Seventy four consecutive patients.Main outcome measures: Kappa measurement of agreement was used to determine the agreement between MRI and MRI, MRS with the final diagnosis. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the two tests were calculated. The difference between the number of indeterminate lesions in the twotests was determined. Logistic regression demonstrated the role of confounding factors in the diagnostic use of MRS.Results: MRI, MRS had a higher agreement with the final diagnosis than MRI in isolation. The sensitivity of MRI, MRS was 4.82 times greater than that of MRI. MRI, MRS had a 1.7% increase in accuracy. MRI, MRS reduced the indeterminate MRI lesions by 5.4%. Logistic regression showed that for lesions which were enhancing, MRS yield was more helpful if the voxel position included the enhancing part.Conclusion: MRI,MRS is better than MRI alone in characterisation of neoplastic from non- neoplastic focal brain lesions

Prevalence and Factors Associated with Depression among Patients with Epilepsy at Aga Khan University Teaching Hospital Nairobi

Objective: To determine the prevalence and factors associated with depression in patients with epilepsy  at Aga Khan University Hospital; Nairobi.Design: A Cross-Sectional Survey.Setting: Neurology clinic, Aga Khan University Hospital; NairobiSubjects: Eligible patients with epilepsy on follow-up at the neurology clinic were recruited.Intervention: Beck-Depression-Inventory was administered to evaluate presence of depression.Main Outcome Measures: In addition to depression, patients with co-morbid depression were further evaluated for associated factors.Results: Three-hundred-and-twenty-seven patients were evaluated for presence of depression. Fifty-four patients in the study cohort had depression, giving prevalence of depression; based on the  Beck-Depression-Inventory as 16.5 %, (95 % CI 12.7-21.0) There was weak association between mild depression and polytherapy (use of two or more antiepileptic drugs), with OR 2.3, 95%CI 0.9-5.8  however, none between polytherapy and moderate or severe depression. No statistically significant  association was found between depression and duration of epilepsy or number of seizures per month over last three months.Conclusion: The prevalence of depression in patients with epilepsy at Aga Khan University Hospital, Nairobi was 16.5 %( 95% CI 12.7-21.0) and polytherapy was weakly associated with mild depression. Depression among patients with epilepsy warrants clinical attention especially in patients on polytherapy. The risk of AED polytherapy was two-fold greater (OR 2.3, 95%CI 0.9-5.8) in patients with mild  depression compared to patients with epilepsy without depression

A review of electroencephalograms done at the Kenyatta National Hospital, Nairobi

Background: Electroencephalogram based studies done elsewhere suggest that epileptiform activity originates predominantly from the left cortical hemisphere. There is evidence that partial epilepsies (focal spike and wave epileptiform discharges on tracings) connotes focal;secondary structural cortical dysfunction.Studies seeking similar findings have not been done locally. Objective: To review electroencephalograms (BEGs) done at Kenyatta National Hospital (KNH); looking for various types of epileptiform discharges and their cerebral cortex of origin. Design: Retrospective observational study. Setting: Kenyatta National Hospital, Nairobi, Kenya- from January 1986 to June 2004 Results: A total10431EEG records were reviewed. Ninety Eight percent of referrals for EEG evaluation was for clinical differential diagnosis of epilepsy. AbnormalBEGs comprised 32.2% of the study population. Epileptiform abnormalities (i.e.focal spike and wave,generalized spike and wave and 3Hz spike and wave) discharges accounted for75.2% of all abnormal EEG waveform discharges.Of the epileptiform abnormalities, focal spike and wave discharges comprised 71%. Focal spike and wave discharge implies a possible secondary aetiology of epilepsy.The left cerebral hemisphere was the origin of 49.8% of focal spike and wave epileptiform EEG discharges. Multifocal loci in cerebral cortices (i.e. frontal, temporal and parietal) were the foci of origin of abnormal EEG waveforms in 69.9% of recordings. Conclusion: Focal spike and wave epileptiform discharges, with attendant likely secondary aetiology of epilepsy is predominantly evident in this study. It contrasts findings from western literature.The left cerebral hemisphere is more epileptogenic as is noted in other studies

Primary cerebral angitis of the central nervous system: case report

We report a case of a 28 year old female who presented with variedly progressive stroke like illness and raised intracranial pressure. Brain MRI scans revealed pericallosal and periventricular hyperintensities with oedema. Various medications like intravenous immunoglobulin, antibiotics, acyclovir, methyl prednisolone and management for raised intracranial pressure were instituted. She rapidly deteroriated and died on tenth hospital day. Only at autopsy was the diagnosis of primary angitis of central nervous system established

Risk factors for cardiac dysfunction in children on treatment for cancer at Kenyatta National Hospital, Nairobi

Objective: To determine the point prevalence of abnormal cardiac function and to assess the risk factors for cardiac dysfunction in paediatric oncology patients on treatment at Kenyatta National Hospital. Design: Descriptive cross-sectional study with a nested case control. Setting: Kenyatta National Hospital between February and April 2006. Main outcome measures: Left ventricular dysfunction if ejection fraction (EF) 29%. Results: One hundred and eleven patients were enrolled of whom 32 had abnormal cardiac function and were classified as cases while 79 had normal cardiac function. About a third, point prevalence 29% (95% CI 21.2-37.9), had cardiac dysfunction. Cumulative anthracycline dose was a risk factor for cardiac dysfunction in this population. Above 200mg/m2 the attributable risk percentage of cardiac dysfunction was 77%. Conclusions: Serial echocardiography should be performed to identify patients at risk. Alternative treatment protocols should be used when the cumulative anthracycline dose exceeds 200mg/m2 due to the high attributable risk. Studies to further assess the other associated risk factors and long term effects of anthracycline are recommended

Radiation exposure in interventional procedures

The aim of this study was to estimate radiation doses patients and staff are exposed to during interventional procedures (IPs), compare them with the international diagnostic reference levels and to develop initial National Diagnostic Reference Levels. The IP survey was undertaken as the initial task of which, retrospective data were collected from the only four Kenyan hospitals carrying out interventional radiology and cardiology procedures at the time of the study. Real-time measurement of radiation dose to patients and staff during these procedures was done. To the patients, kerma-area product (KAP) and fluoroscopy time measurements were done using an in-built KAP meter, while peak skin dose (PSD) was measured using slow Extended Dose Range (EDR2. ®) radiographic films. The staff occupational doses were measured using individual thermoluminescence dosemeters. The maximum and minimum KAP values were found to be 137.1 and 4.2 Gy cm. 2, while the measured PSD values were 740 and 52 mGy, respectively. The fluoroscopic time range was between 3.3 and 70 min. The staff doses per procedure ranged between 0.05 and 1.41 mSv for medical doctors, 0.03 and 1.16 mSv for nurses, 0.04 and 0.78 mSv for radiographers and 0.04 and 0.88 mSv for clinical staff. The measured patient PSDs were within the threshold limit for skin injuries. However, with the current few IP specialists, an annual increase in workload as determined in the study will result in the International Commission on Radiation Protection annual eye lens dose limit being exceeded by 10 %. A concerted effort is required to contain these dose levels through use of protective gear, optimisation of practice and justification

Osmotic demyelination syndrome: Case report

We present a 40 year old man who was admitted to the hospital with convulsions. His final diagnosis was osmotic demyelination syndrome (ODS).We discuss the diagnostic and management challenges and the possible complications of this rare diagnosis

Lessons Learned Developing a Diagnostic Tool for HIV-Associated Dementia Feasible to Implement in Resource-Limited Settings: Pilot Testing in Kenya

Objective: To conduct a preliminary evaluation of the utility and reliability of a diagnostic tool for HIV-associated dementia (HAD) for use by primary health care workers (HCW) which would be feasible to implement in resource-limited settings. Background: In resource-limited settings, HAD is an indication for anti-retroviral therapy regardless of CD4 T-cell count. Anti-retroviral therapy, the treatment for HAD, is now increasingly available in resource-limited settings. Nonetheless, HAD remains under-diagnosed likely because of limited clinical expertise and availability of diagnostic tests. Thus, a simple diagnostic tool which is practical to implement in resource-limited settings is an urgent need. Methods: A convenience sample of 30 HIV-infected outpatients was enrolled in Western Kenya. We assessed the sensitivity and specificity of a diagnostic tool for HAD as administered by a primary HCW. This was compared to an expert clinical assessment which included examination by a physician, neuropsychological testing, and in selected cases, brain imaging. Agreement between HCW and an expert examiner on certain tool components was measured using Kappa statistic. Results: The sample was 57 % male, mean age was 38.6 years, mean CD4 T-cell count was 323 cells/mL, and 54 % had less than a secondary school education. Six (20%) of the subjects were diagnosed with HAD by expert clinical assessment. The diagnostic tool was 63 % sensitive and 67 % specific for HAD. Agreement between HCW and expert examiners was poor for many individual items of the diagnostic tool (K =.03–.65). This diagnostic tool had moderate sensitivity and specificity fo