A comparative investigation of methods for longitudinal data with limits of detection through a case study.

The statistical analysis of continuous longitudinal data may be complicated since quantitative levels of bioassay cannot always be determined. Values beyond the limits of detection (LOD) in the assays may not be observed and thus censored, rendering complexity to the analysis of such data. This article examines how both left-censoring and right censoring of HIV-1 plasma RNA measurements, collected for the study on AIDS-related Non-Hodgkin's lymphoma (AR-NHL) in East Africa, affects the quantification of viral load and explores the natural history of viral load measurements over time in AR-NHL patients receiving anticancer chemotherapy. Data analyses using Monte Carlo EM algorithm (MCEM) are compared to analyses where the LOD or LOD/2 (left censoring) value is substituted for the censored observations, and also to other methods such as multiple imputation, and maximum likelihood estimation for censored data (generalized Tobit regression). Simulations are used to explore the sensitivity of the results to changes in the model parameters. In conclusion, the antiretroviral treatment was associated with a significant decrease in viral load after controlling the effects of other covariates. A simulation study with finite sample size shows MCEM is the least biased method and the estimates are least sensitive to the censoring mechanism.

Clinico-pathologic characteristics and treatment outcomes in children with neuroblastoma at the Kenyatta National Hospital, Nairobi.

OBJECTIVE: To determine clinical-pathologic characteristics, treatment modalities and treatment outcomes of children diagnosed with neuroblastoma. DESIGN: Cross-sectional descriptive study based on secondary data from patient records. SETTING: Records department of Kenyatta National Hospital (KNH), a tertiary teaching and referral hospital based in Nairobi. SUBJECTS: Children aged 15 years and below, admitted with the diagnosis of neuroblastoma, between January 1997 and December 2005. MAIN OUTCOME MEASURES: Presenting clinical features, diagnostic modalities including laboratory and imaging data, treatment modalities, response to treatment and patient survival. RESULTS: Twenty six patients were eligible for the study; 13 males and 13 females giving a M:F ratio of 1:1. The age range was 5 days to 12 years, with a median age of five years. Abdominal swelling (53.8%), inability to walk due to bone pains, (50%), and cranial or periorbital swelling, (38.5%) were the commonest presenting features. Diagnosis of neuroblastoma was based on tissue biopsy in 50% (95% CI 40.6-79.8%) of the patients, and on fine needle aspiration cytology of mass or bone marrow in the rest. Bone marrow involvement was present in 16, (75%). Anaemia, was common with 72.7% patients having a haemoglobin (HB) <8 g/dl at presentation. Immunohistochemistry and cytological grading were done in two, (8%), patients. Urinary vanilly 1 mandelic acid (VMA), screening was positive in 50% (95% CI 29.9%-70.1%). The most frequently involved organs were abdomen (88.9%), and skeleton, (84.6%). Majority of patients, (92.3%), presented with advanced stage IV disease. Three patients died before commencement of treatment. All treated patients (100%), received cytotoxic therapy. Only two patients (8.6%) had surgery as part of treatment while one, (4.3%) was treated with radiotherapy. The initial treatment regimen was similar for all the patients. Although most patients had a complete initial response to treatment, early relapse, treatment failure, death or loss to follow up of patients with progressive disease were common. Overall survival (OS) at one year and two years were 19.2% (95% CI 6.6-39.4%) and 7.7% (95% CI 0.9%-25.1%) respectively. Only one patient was alive, (also free of disease), five years after diagnosis. CONCLUSION: Although other clinical-pathologic findings of the patients were similar to those reported elsewhere, virtually all study patients presented with advanced stage IV disease, which would be associated with poor prognosis irrespective of quality of care. Priority must therefore be on ensuring early diagnosis and referral of patients with neuroblastoma before any other interventions can be expected to positively impact on outcome. The limited role of surgery and radiotherapy observed over the study period may be attributed to late presentation of the patients. Pathologic evaluation of important information could have been availed at minimal extra cost. To be at par with current internationally accepted treatment approaches that have been associated with improved survival, there is need to base choice of regimens for individual patients on clinical and readily accessible pathologic markers.

Serum total sialic acid and Hanganutziu-Deicher antibody in normals and in cancer patients.

OBJECTIVE: To determine the levels of both TSA and HD antibody in sera of patients with various malignancies and evaluate their potential role as diagnostic and/ or prognostic markers. DESIGN: Laboratory based analysis. SETTINGS: Kenyatta National Hospital, Kenya Medical Research Institute and the Department of Biochemistry, University of Nairobi. SUBJECTS: A total of 909 serum samples, 420 from cancer patients recruited at Kenyatta National Hospital and 509 from normal blood donors recruited at Nairobi Hospital. RESULTS: The mean age for the patients and controls was 36 and 37 years respectively. Carcinoma patients constituted 54%, sarcoma 12.1%, lymphoma 16.4% and 17.4% had other types of tumours. The mean TSA in patients was 0.86 mg/ml +/- 0.026 compared to 0.82 mg/ml +/- 0.014 in controls. The TSA level was significantly higher in patients compared to controls (Student's t-test p = 0.031 at 0.05 confidence level). The TSA increased with age in both study groups. In patient sera, both gender gave the same mean of 0.83 mg/ml while it was 0.82 mg/ml and 0.83 mg/ml in control females and in males respectively. Sarcomas had the highest amount of 0.93 mg/ml but there was no significant statistical variation between tumour types (p = 0.076). The HD antibody mean readings were 0.004 in pathologic sera compared to 0.011 in controls. The values were significantly elevated in patients (p = 0.03) with females giving a higher value for both study groups (p = 0.628). HD antibody readings was significantly higher in carcinomas (p = 0.017) compared to those of sarcomas and lymphomas. There was no association between antibody readings and age of patient (p = 0.601). CONCLUSION: Both TSA and HD antibody values were significantly elevated in patients compared to clinically healthy controls and while TSA levels increased with age and was independent of gender, HD antibody levels were independent of age, gender and also tumour type. The study demonstrates that although TSA is normally elevated in malignancy, most of the sialic acid shed is of N-acetyl type as some patients do not express HD antibody directed to the N-glycolyl sialic acid. The reason why some tumours would express Neu5Gc at any one time needs further evaluation.

Acute aflatoxicosis: case report.

The objective of this presentation is to document the salient clinical findings in a case of aflatoxicosis and to review the literature on the same so as to increase the index of suspicion, enhance early diagnosis and improve management. The case was a 17-year-old schoolboy presenting with vomiting, features of infection and gastrointestinal tract symptoms. Examination revealed a very ill looking pale patient with abdominal distension, tenderness and rectal bleeding and easy bruisability. Investigations showed abnormal liver function tests, pancytopenia and elevated serum levels of aflatoxins. Management consisted of supportive care including antibiotics and antifungal therapy, transfusion of red blood cells and fresh frozen plasma. His recovery was uneventful. The literature on human aflatoxicosis shows that the presentation may be acute, subacute and chronic. The degree of emanating clinical events also conforms to status of the aflatoxicosis. Overall, the features are protean and may masquerade many other forms of toxaemias. In conclusion, the diagnosis of aflatoxicosis takes cognisance of geographical location, past events, staple diet and clinical features to exclude other infections. Also required are high index of suspicion and importantly serum levels of aflatoxin. Treatment strategies involved use of antimicrobials and supporting the damaged multi-organs.

Kaposi's sarcoma in patients with and without human immunodeficiency virus infection, in a tertiary referral centre in Kenya.

The clinical features of Kaposi's sarcoma (KS), in patients with and without HIV infection, were investigated in a tertiary referral centre in Kenya between 1997 and 1999. Although 186 cases were identified prospectively, the data analysis was restricted to the 91 (49%) cases who had pathological confirmation of Kaposi's sarcoma and documented HIV serostatus. Among these 91 subjects (58% of whom were male), the age-group holding the largest number of KS cases was that of individuals aged 31-40 years; most of the paediatric cases were aged 6-10 years. The ratio of HIV-seropositives to HIV-seronegatives was 8.5:1 for the adult cases and 0.9:1 for the paediatric. Of the signs and symptoms of Kaposi's sarcoma seen at presentation, only peripheral lympadenopathy was found to be significantly associated with underlying HIV infection (P = 0.05). The median survival was 104 days. It is apparent that, as the HIV epidemic advances in regions of the world with endemic KS, the clinical presentation and natural history of the endemic KS are blending with those of the epidemic or AIDS-associated disease, leading to a reduction in the mean age of the cases and a nearly identical incidence in men and women. In regions of the world where patients have ready access to such chemotherapy, the impact of treatment with highly active antiretroviral drugs on the incidence and natural history of KS has been dramatic. It will be important to monitor the clinico-pathological features of KS in the developing world, as more active antiretroviral regimens become available in clinical practice there.

Comparing walk-in and call-responsive donors in a national and a private hospital in Nairobi.

BACKGROUND: The non-remunerated donors in many of Kenya's hospital blood banks are either call responsive (CR) or walk-in (WI) donors. These donors impact differently on the national blood transfusion services. OBJECTIVE: To examine the walk-in (WI) and call responsive (CR) donors' influence on the national blood transfusion services. DESIGN: A retrospective study. SETTING: A national referral and a private hospital in Nairobi, Kenya. MAIN OUTCOME MEASURES: Donor's age, sex, whether walk in or responded to a call to donate for a relative or emergency blood requirement and test results of; HIV, HBsAg, syphilis and HCV. RESULTS: Between April 1999 and April 2000, 10,295 persons donated blood either responding to a call or walked in. The national referral hospital had 8,563 (83%) and private hospital 1,732 (17%). In total, 2.5% were WI and 97.5% CR. The lowest age of donors were CR 15, and WI 18 years. Of 1,138 (11.1%) rejected were 4.6% WI and 11.2% CR donors. The infections 5.8% HIV, 4% HBSAg, 1.2% VDRL and 0.2% HCV were statistically significant in WI compared to CR (p=0.002), also in female compared to male donors (p=0.001). CONCLUSION: This study shows that walk in donors were fewer than call responsive but had less rates of transfusion associated infections.

Radiological features of Burkitt's lymphoma.

BACKGROUND: Diagnostic radiology investigations play important roles in the management of Burkitt's Lymphoma. OBJECTIVES: To document the various radiological manifestations of Burkitt's lymphoma as seen in patients at the Kenyatta National Hospital. DESIGN: Prospective study of Burkitt's Lymphoma cases admitted to the paediatric and Ear, Nose and Throat Wards. SETTING: Kenyatta National Hospital. MAIN OUTCOME MEASURES: All histological proven cases of BL had the following documented; Age sex, tribe, geographical (province) of origin, full medical evaluation results, presenting site of tumour, radiological findings and results of chest X-ray, abdominal ultrasound occipital frontal view of the skull X-ray. computerised tomography, myelography and orthopantomograms. RESULTS: In the period between April 1991 and March 1992 this study registered 49 patients age range 2 to 14 years. These were males 34 (69%) and females 15 (31%). The commonest radiological findings was associate with intra abdominal lymphoma seen in 65.2% of the cases, the least findings associated with cervical adenopathy and pleural effusion each 3.3% of cases. Twenty (41%) of the disease was clinically confined to the facial area while radiologically 25% of these were demonstrated to extend to the abdomen as well. CONCLUSION: Disease extent on radiological examination was found to be more extensive compared to clinical evaluation alone. The observation emphasised the role of radiological investigation in the management of lymphomas in this setting.

Burkitt's lymphoma: the initial defining characteristics.

OBJECTIVES: To put together salient historical, geographical and biological characteristics of Burkitt's lymphoma. DATA SOURCES: Burkitt's lymphoma study data gathered over a ten year study, other publications, original and review articles, conference abstracts searched mainly on PubMed indexed for Medline. DATA EXTRACTION: A systematic documentation and review to identify information relating to Burkitt's lymphoma, historical, geographical and biological characteristics. Only data relevant to the objectives of the subject were extracted. DATA SYNTHESIS: A detailed qualitative assessment was undertaken given the heterogeneity of data and study types making it not appropriate to pool results across studies. CONCLUSION: Burkitt's lymphoma is historically linked to the tropical Africa and its geographical characteristics have been the most defining characteristics of its other features. The biological characteristic also roots strongly in its geographical and clinical manifestations.

Burkitt's lymphoma in Kenya: geographical, age, gender and ethnic distribution.

OBJECTIVE: To show the geographical (Provincial), age, gender and ethnic distribution of Burkitt's lymphoma in patients in Kenya. DESIGN: A retrospective review of patients' records for the years 1988-1992 and a prospective evaluation of patients with BL between 1993 and 1997. These were descriptive and hospitals based studies. SETTING: Kenyatta National Hospital; Kenya's main referral and teaching hospital and seven provincial hospitals. MAIN OUTCOME MEASURES: For each tissue proven Burkitt's lymphoma case the following were required; province of birth and residence, tribe, age, sex, chief complains, physical examination findings, investigation results and tissues result confirming the diagnosis of BL. STATISTICAL METHOD: Mainly proportions were used to compare variables, however Pearson's liner correlation was used to assess the time trends. RESULTS: This study registered 1005 patients; 961 (95.6%) children and 44 (4.4%) adults. 0-14 years the age standardized incidence rate (ASR) of 0.83. Variations documented in the provinces' BL ASR range; 1.8 Coast to 0.23 Rift Valley and increasing yearly trend for both children and adults. The major tribes in Kenya consisted; Luo 29.5%. Luhya (24.1%) and Coastal (16.5%). No patient of Asian or European or Arab extraction was recorded in the study. The age distribution showed no case below two years, a rapid rise from three year 3 (5.6%), and peak at 6 (19.5%) for children and at 17 years (13.6%) years for the adult. Age group 5-9 years had the highest ASR. The male to female (M:F) ratios were; 1.5:1 and 1:1 in children and adults respectively, provincial ratios range; 2.6:1 in Nairobi to 1.2:1 in Nyanza, the tribes range; 3.5:1 in Somali to 1:1 in other tribes between 2 and 14 years old when also males were more than females. Peak time of presentation of symptoms was 4 weeks. Tumour sites were in children; jaw 51.6%, abdomen (25%), combined jaw and abdomen 13.8% and others 9.6% and adults; jaw (4.5%), abdomen (43.2%), combined jaw and abdomen (25%) and other sites (27.3%) 67.6% males and 42.4% female adults had HIV infection and disseminated BL disease. CONCLUSION: The study demonstrates that Burkitt's lymphoma is a childhood disease. The disease distribution is consistent with intermediate risk Burkitt's lymphoma level. Furthermore the distribution varied by province, tribe, age and gender. The variations could be due to environmental factors.

Anatomical site predilections of non-Hodgkin's lymphoma in human immunodeficiency virus infection: a report on 54 cases.

OBJECTIVE: To identify and describe the primary anatomic sites of non-Hodgkin's lymphoma arising in the setting of Human Immunodeficiency Virus infection. DESIGN: Prospective (ongoing) study. SETTING: Kenyatta National Hospital a referral and teaching hospital in Kenya. SUBJECTS AND METHODS: Patients (n=54) with human immunodeficiency virus with associated non-Hodgkin's lymphoma managed at the Kenyatta National hospital from January 2001 to December 2003. Relevant clinical information obtained by medical history, physical examination and investigations. RESULTS: Of the 54 patients studied 29(54%) were males and 25(46%) females with median age 36 and range 20 to 61 years. Fifty (93%) had high grade and four (7%) intermediate grade lymphoma, the former had 15 (30%) Burkitt's and the rest large cell lymphoma. The stages at diagnosis were IV 35(65%), III 14(26%) and II 5(9%) and all had B symptoms. The primary sites at presentation to the hospital were peripheral nodes 16(30%), abdominal 15(28%), pectoral/chest wall 11(20%), central nervous system eight (15%) and systemic/generalised, four (7%). CONCLUSION: This study demonstrates that there were preferred anatomical sites of involvement by HIV associated non-Hodgkin's lymphomas and the finding of pectoral/ chest involvement in this series may not be coincidental. Further, this study suggests that anatomical sites predilection may be due to the tendency of viral associated malignancies to home to specific anatomic sites and also due to the anatomy of the lymphoreticular system. Studying virus pathogenesis in malignancies should consider also the anatomic sites involved.

Clinical characteristics of Burkitt's lymphoma seen in Kenyan patients.

OBJECTIVE: To document the clinical features of Burkitt's lymphoma (BL) in the study population. DESIGN: Retrospective and prospective documentation of clinical details using a standard clinical assessment model. SETTING: Kenyatta National Hospital and all the seven provincial hospitals in Kenya. SUBJECTS: The study involved all cases with tissue proven diagnosis of Burkitt's lymphoma during the study period of ten years. MAIN OUTCOME MEASURES: For each BL case, the following were docummented age, sex, geographical (province) area, complaints, physical examination, investigation result findings. RESULTS: This study documented 961 children and 44 adults with Burkitt's lymphoma. Male to female ratio was 1.5:1 in children and 1:1 in adults. All the eight provinces in Kenya had cases of BL and of the 44 tribes 22 were represented. The study showed that BL is a rapidly growing tumour with peak duration of 4 weeks and main complaint was swelling. The major sites involved were Jaw 51.6%, abdomen 25%, combined jaw and abdomen 13.8% and other sites 9.6%. In adults, involved sites were jaw 4.5%, abdomen 43.2%, combined jaw and abdomen 25% and other sites 27.3%. CNS disease demonstrated in 39%, bone marrow 25% while abnormal liver function tests were 18% and abnormal kidney functions 20%. Involved sites in children, jaw peaked at three years 66.7% and abdomen at 14 years 66.7% while in adults abdominal presentation was dominant at all ages. Furthermore jaw were 55% males verses 16% females. Stage at presentation; A 35.2%. B 31.1%, C 31% and D 2.7%. Adult cases had stage D 75% and C 25% but no stage A and B. Adult cases showed HIV 59% positive, mostly over 25 and peaking at 34 years of age with 67.6% males and 42.4% females. HIV BL cases had disseminated disease with lymph nodes, scalp, bone marrow involvement and pancytopenia as major features. CONCLUSION: The clinical features are protean and BL is a rapidly progressive disease, presenting with swelling, majority in the jaw and abdomen in childhood and young adults. Age, sex and geographical (province) appear to influence the primary site of the disease. Also BL is a differential in many clinical presentations in this childhood setting.

Aspects of epidemiological and clinical features of patients with central nervous system Burkitt's lymphoma in Kenya.

BACKGROUND: Establishing characteristics of Central nervous System (CNS) Burkitt's lymphoma (BL) is essential as CNS disease is associated with poor treatment outcome. OBJECTIVE: To document the characteristics of those cases of Burkitt's who had CNS disease at the time of presentation. DESIGN: Prospective study of the clinical details of paediatric patients admitted and treated for Burkitt's lymphoma from January 1986 to December 1997. SETTING: Kenyatta National Hospital and seven provincial hospitals in Kenya. MAIN OUTCOME MEASURES: For every histologically proven Burkitt's case, the following were documented; Age, sex, geographical area (province in Kenya), complaints, physical findings, Cerebral Spinal Fluid (CSF) cytology results, Human Immunodeficiencies Virus screening test result and anatomical sites of the disease at the time of starting therapy. RESULTS: A total of 1005 BL cases were studied and 961(95.6%) were aged between two and 15.4 years median age of six years consisting of males 587(61%) and females 374 (39%) while 44 (4.4%) cases between 16 and 57 years consisting of males 23 (52%) and females 21 (43%). The main complaints; headache, swelling mainly facial, abdominal distension and proptosis. Peak duration at presentation 4 and 8 weeks, range 1 to 26 weeks. Clinical evaluation demonstrated CNS in 5.6%, presenting as headache, blurring of vision and difficulties in walking. Physical examination noted para-paresis, ophthalmoplegia and cranial nerve palsies, while CSF demonstrated BL cells in 158 (18.4%). Overall CNS BL was found in 161 (16.8%), children and 39% adults. All were systemic and no primary CNS BL detected. Peak age was 11 to 15 years for children. Their provinces Eastern; 24.5%, Central 21.3%, and Rift Valley 23.4%, ethnic origins, Meru 29.5%, Kikuyu 23.9% and Kamba 23.7%. The sites of tumour for CNS cases were abdominal, combined sites, and skeletal while least in maxilla and jaw. Seventy one per cent of adults had both CSF BL and HIV infection. CONCLUSION: CNS-BL children cases were older, reduced M:F ratio; had skeletal/abdominal presentation and were from the Central province, Kikuyu tribe and a positive CSF cytology for malignant cells found in almost all cases with CNS disease at presentation. No primary CNS BL detected. Geographically, cases were from mainly the highlands of Kenya. High CNS disease in adults coincided with HIV positive serostatus.

Challenges in the epidemiological and clinical aspects of Burkitt's lymphoma in Kenya: linking evidence and experience.

BACKGROUND: In a series of 1005 cases of Burkitt's lymphoma studied for epidemiological and clinical characteristics, some features remain less obvious contrary to what is commonly held about this disease. OBJECTIVES: To use the case series to document the challenges in the epidemiological and clinical characteristics of Burkitt's lymphoma (BL) in Kenya. DESIGN: Cross sectional study involving clinical review of case series. SETTING: Kenyatta National Hospital and the seven provincial hospitals in Kenya during the period between 1986 and 1996. DATA SOURCES: Systematic review of the epidemiological and clinical features of the 1005 cases enrolled in the case study and review of reference lists of retrieved articles to identify original research dealing with the epidemiological and clinical features of Burkitt's lymphoma. DATA EXTRACTION: The investigators and research assistants screened both the case series and published information and data to yield relevant information. CONCLUSION: The majority of Burkitt's lymphoma cases between the age group three and nine years of age coincide with the established epidemiological and clinical characteristics. The adult BL cases and some childhood cases however do not conform entirely to the established characteristics. Therefore, making the diagnosis of Burkitt's lymphoma require that; geographical, demographical, clinical features as well as any underlying infections for instance, Human Immunodeficiency Virus be taken into consideration.

Transfusion haemosiderosis inspite of regular use of desferrioxamine: case report.

We describe a case of a female who developed haemosiderosis, in the course of treatment for very severe unstable aplastic anaemia for fourteen years. She was 37 years old at the time of initial diagnosis. Her management consisted of regular blood transfusions aimed at haemoglobin above 8.5 g/dl, antimicrobials, oxymetholone, low dose prednisone and folate. She had received about seventy five units of blood at the start of 2 grams of desferrioxamine with every subsequent blood transfusion. Annual tests of serum ferritin showed progressive increase. She developed skin changes, diabetes mellitus, heart disease, recurrent infections, generalized joint and abdominal pains and liver failure. She died within six weeks of developing congestive heart failure coupled with liver failure due to haemosiderosis despite regular use of desferrioxamine.

Lupus anticoagulants: pathophysiology, clinical and laboratory associations: a review.

OBJECTIVES: To put together salient clinical and laboratory manifestations and also to highlight the pathophysiology and principles of management of lupus anticoagulants syndrome. DATA SOURCES: Publications, original and review articles, conference abstracts searched mainly on PubMed indexed for Medline. DATA EXTRACTION: A systematic review to identify studies relating to lupus anticoagulants, clinical, laboratory, pathophysiology and management. Only data relevant to the objectives of the review were extracted. DATA SYNTHESIS: A detailed qualitative assessment was undertaken given the heterogeneity of study types making it not appropriate to pool results across studies. CONCLUSION: It is demonstrated that lupus anticoagulants (LA) are associated with thrombotic events, recurrent foetal loss and female infertility and also occasionally with bleeding due to thrombocytopenia or hypoprothrombinaemia LA interferes with phospholipid dependent laboratory test of coagulation and the test are not corrected by addition of normal plasma. False positive antiphospholipid antibody test is noted frequently in patients. LA has been detected in all races and geographical regions in the world. The treatment involves use of corticosteroids, anticoagulants, immunoglobulins and occasionally cytotoxic drugs and plasmapheresis long-term prophylaxis and follow up of patients with IgG antiphospholipid antibodies are recommended. Screening for LA considered in patients with unexplained; thrombotic events, foetal loss and bleeding.

Cancers in children younger than age 16 years in Kenya.

OBJECTIVE: To determine the number of cancers seen in six months in children aged below sixteen years and to look for any associations with breastfeeding, parental ages, smoking, water availability and consanguinity. DESIGN: Prospective case study from June 1997 through December 1997. SETTING: Seven provincial hospitals and Kenyatta National Referral Hospital. SUBJECTS: Both sexes with tissue proven malignancy. INTERVENTIONS: By obtaining clinical information, and laboratory evaluatory results. MAIN OUTCOME MEASURES: Proportions of vital statistics, anatomic site, stage and histology of cancer, vaccination, breastfeeding, congenital abnormality, parental vital statistics, education, smoking, water availability status and consanguinity. RESULTS: One hundred and fifty seven cases were evaluated. Male to female (M:F) ratio was 1.5:1. Mean ages: patients 6.5, fathers 36.6, mothers 31.1 years. Histologic types were: Burkitt's lymphoma (BL) 45%, nephroblastoma 14%, Hodgkin's lymphoma 9.5%, acute lymphocytic leukaemia 7.6%, retinoblastoma 5.7%, acute myeloid leukaemia 5.1%. The age distribution was as follows: 0-5 years, 46.5%, 6-10, 39.5% and 11-16 years 14%. The birth places of the children were as follows: Nyanza 25%, Central 21%, Eastern 16%, Western 13%, Rift Valley 9%, Coast 8%, Nairobi 8% and North Eastern had less than one per cent. The ethnic distribution was; Luo 25%, Kikuyu 22%, Luhya 13%, Kamba 10%, Coastal 6%, Kalenjin 6%, others 19%. Fifty per cent of the cases studied were breastfed for over six months, 34% for 3-6 months, five per cent less than three months and eleven per cent were not breastfed. Eighty five per cent of the cases received complete vaccination. The modal number of siblings was four and only 49% of parents received formal education. No consanguinity was noted in the studied population. The abdomen and jaw were main anatomic sites involved by the tumours. CONCLUSION: This study showed that the commonest childhood tumour is Burkitt's lymphoma and nephroblastoma is the commonest solid tumour. While the results demonstrate geographic and ethnic variations, other factors studied do not appear to influence the characteristics of cancers in the cases investigated.

Megaloblastic marrow in macrocytic anaemias at Kenyatta National and M P Shah Hospitals, Nairobi.

OBJECTIVE: To determine the diagnostic value of megaloblastic marrow in patients with possible vitamin B12 and/or folate deficiency and to look for criteria that could be used in diagnosis of vitamin B12 deficiency. DESIGN: Prospective study. SETTING: Kenyatta National Hospital and M P Shah Hospital, Nairobi. SUBJECTS: Patients of all age groups and both sexes presenting with clinical and blood picture of macrocytic anaemia. MAIN OUTCOME MEASURES: Response to vitamin B12 injections. Vitamin B12 deficiency diagnosed by the following methods: Vitamin B12 serum level assays alone, bone marrow examination alone and both vitamin B12 assays and bone marrow examination. Response was measured clinically and by increase in haemoglobin level after three weeks of treatment. RESULTS: Three hundred and forty-three patients were evaluated; 156 (45.5%) were males, and 187 (54.5%) females. Age range was 13-80 years and a mean of 37.7 years. Initial investigations were as follows: 21.9% had vitamin B12 assays only, 59.2% bone marrow examination only and 19.9% both vitamin B12 assayed and bone marrow evaluated. Haemoglobin increase after a total of 6,000 mcg of vitamin B12 was between 2.6-4.6 g/dl in three weeks. Reticulocytes measured on day ten ranged between 12% and 17%. Uniform improvement in all patients was observed for white blood cells (WBC) and platelet counts. Other significant results and observations included clinical improvement in the signs and symptoms of anaemia after the 6,000 mcg injection of vitamin B12 given over three weeks. Serum folic acid level was determined in 21% of cases and in all these it was normal. CONCLUSION: The important practical points were response to vitamin B12 in all cases and the importance of re-assessing patients after a total of 6,000 mcg of vitamin B12. Folic acid deficiency was not detected. Patients in these two institutions with megaloblastic anaemia had vitamin B12 deficiency. It is proposed that a model consisting of oval macrocytosis on blood film and megablastic bone marrow be treated with vitamin B12 injections in settings where vitamin B12 serum level assays are not easily available.

Relapse of Hodgkin's disease after 10 years of complete remission: case report.

A 17 year old male patient with nodular sclerosis Hodgkin's disease had a relapse of lymphocyte depleted type ten years after entering complete remission with chemotherapy and radiotherapy. This is the first documented case in our experience of relapse after very long disease free interval. A review of the literature of late relapses in Hodgkin's disease is also presented. Relapses have been recorded from three years to twenty years, although few very late forms are registered. Long term follow up will be necessary to document the role of the different therapeutic regimen.