Morbidity of downs syndrome among hospital population of patients in Bahrain
تعرض هذه الورقة دراسة لمعلومات جمعت بشكل استعاري من سجلات المستشفى لـ 104 من المرضى البحرينيين المصابين بمتلازمة داون بين عام 1989 و 1993 وقد شملت هذه الدراسة جميع المرضى الذين تم إدخالهم إلى المستشفى الرئيسي في البحرين خلال الخمسة أعوام الماضية. حيث اجري تحليلا على النمط (الصبغي) لـ 89 مريض.
لقد وجد إن العمر المتوسط للمرضى المدخلين إلى المستشفى هو خمس سنوات، 60% من هؤلاء المرضى كانوا دون السنة الواحدة من العمر وأكبرهم في الواحد والثلاثين. كانت المضاعفات الأكثر شيوعا بينهم هو التهابات الصدر وأمراض القلب الولادية وزيادة قابليتهم للإصابة بجميع أنواع الاخماج كذلك فقر الدم بالإضافة إلى مضاعفات في العين والأذن والحنجرة.
وقد اوضح التحليل النووي (الصبغي) أن 97% من هؤلاء المرضى لديهم التثلث الصبغي 21 و أن 2% لديهم إزفاء (تغير موضع الصبغيات) و 1% كان فريقا مع نمط صبغي نادر (74 ××، + 21, +22). يسجل لأول مرة في العالم.
We have studied date collected retrospectively from the hospital records of 104 Bahraini patient with Down's Syndrome between 1989 and 1993. these included all patients admitted to the main hospital in Bahrain during the last five years. Karyotype analysis was performed on 89 patients. We found that the mean age group of patients admitted is 5 years. Sixty percent of the patients were below one year of age. The oldest patient was 31 year old. The most common complications among them were chest infections, congenital heart disease, increase suspectability to all type of infection, anaemias, ENT and EYE complications.
Karyotyping analysis shows that 97 percent have free Trisomy, 2 percent have translocation and 1 patient is a mosaic with a very rare karyotype reported for the first time (47,xx,+21/47,xx+21,+r22).
Trisomy 21 is one of the common causes of mental retardation in Bahrain1. It is also responsible for significant morbidity and mortality in childhood and high cost for caring for these patients. The birth prevalence of Trisomy 21 is generally stated to be 1:650 live birth2, but this varies in different population from 1:600 to 1:2000 live births. In Bahrain it is 0.9 per 1000 live birth1-4. The purpose of this paper is to present the complications of Down's Syndrome in childhood as an indirect assessment of the social, medical and family costs of looking after these cases.
Common complication among Bahraini patients with Downs' Syndrome
Congenital Heart Disease
Urinary Tract Problem
Less frequent complications among Bahraini patients with Downs' Syndrome
Materials & Methods
The hospital records of all Bahraini patients with Down's syndrome admitted to Salmaniya Medical Centre during the last 5 years were studied and data collected and analysed regarding the ,morbidity of the disease. Cytogenetic analysis were done for 89 patients. The data were stored in IBM personal computer and were analysed using a "database 3" software programme.
The sex distribution of these patients were 60 percent males and 40 percent females. Which indicate that sex ratio is 3 male to 2 females. The mean age was 5 years and that 60 percent of all the patients were below 1 years of age. Most cases were in fact diagnosed and reported in the first year. The oldest patient was 31 year old. Inspite of recent advances in health care of the retarded worldwide and the gradual increase in the life span of those affected with Down's syndrome, the average life expectancy is still 35 years 2-5. The periods of highest mortality risk are in infancy when congenital heart disease. Leukemia and respiratory disease and in late adulthood when Alzheimers disease and declining immunological functions are significant factors. Congenital heart defects (CHD) were found in 41 percent of all cases. Which is similar to internationally quoted figures1.4-5 which shows that 40-60 perecent of patients with 21 Trisomy have CHD. In our series heart defects was found in 41 percent of patients. Infections however accounted for an incidence of 56 percent. Respiratory diseases of 26 percent. Gastrointenstinal infection in 15 percent. Renal infection in 9 percent, encephalitis in 1 percent.
Supectability to infection must be kept in mind and antibiotic therapy must be instituted more readily than for non-trisomic patients. Ninety percent suffered from anaemias which include sickle cell anarmia in 5 percent. Thalassaemia in 3 percent. G6PD and Iron deficiency anaemia in 11 percent. A twentyfold increased risk of developing leukemia was noticed in other studies. While in our series leukemia was found in one patient only. Other forms of cancer were reported in 4% of the cases. The site were breast. Testis, liver and digestive organs1.3.4 Four percent of the patient were admitted following accidents. 2 percent for burns. and 2 percent for drowning. Five percent have hypertension. Karyotype analysis has a diagnostic value. Mostly in the newborn when the clinical diagnosis may be uncertain and it is indispensable for genetic counseling. In most cases 21 Trisomy is due to a free Trisomy which is considered as an isolated meiotic accident. In a minority of cases Trisomy is due to a translocation which can either have occurred de novo, or be transmitted by one parent6-9.
In our study we found that 97 percent of the cases are free Trisomy, 2 oercent are translocation cases with 21,21 translocation. the parents have normal karyotypes. One of the interesting patients is a three year old girl. With a rare karyoptype reported for the first time (47,XX.÷21/47.XX.÷47.XX.÷21.+r(22). She had the clinical picture of Down syndrome. Both parents are above 40. and both have normal karyotype. The child had ring chromosome 22 which is rare10-14.
In free trisomies it might be expected that the risk of recurrence would not be increased. If you allow for maternal age. Among our patients Down's syndrome reoccur only in one family where the first and second child were afflicted with free 21 trisomy. Parents karyotypes were normal. These could be due to the existence of undetected maternal mosaicism or, of genes favouring non-disjunction. When non-disjunction is present in young mothers the risk of recurrence is 1-2%, while for older mothers this risk is limited to that inherent to maternal age6.
The highest morbidity and mortality in cases of Down's Syndrome were in infancy. There seems to be increase susceptibility to infection, of which the most common is chest infection, congenital heart disease. Anaemia was reported in 40 percent of these cases. Prenatal counseling and screening for Downs syndrome may meet an existing preventive health need in our community and will contribute to the reduction of the Down's syndrome population in Bahrain.
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