Trisomy 21 (Down's syndrome): autoimmunity, aging and monoclonal antibody-defined T-cell abnormalities.

Down's syndrome has been associated with organ-specific autoimmunity and 'premature aging'. We studied 27 individuals with Down's syndrome (all trisomy 21, no translocations aged 0.5 to 50 years). Subjects were not preselected for autoimmunity. Six subjects had a history of hypothyroidism and three additional subjects had anti-microsomal antibodies (euthyroid). Three subjects had insulin-dependent diabetes mellitus and one additional subject had islet cell autoantibodies (non-diabetic). The percentage Ia (Dr) positive T cells exceeded the normal range in 7/26 (27%). The percent CD4+ and CD8+ T cells were not significantly different from control. A subgroup of Down's syndrome subjects (less than age 10) had a premature increase in the percentage of 3G5+ (age-related) T cells. Normal individuals express a similar percentage of 3G5+ T cells at age 50 to 70 years. The presence of T-cell activation and 'premature T-cell aging' may predispose Down's syndrome subjects to organ-specific autoimmunity and age-related disorders.

Aortic regurgitation and mitral valve prolapse with Down's syndrome: a case-control study.

This case-control study was designed to determine whether aortic regurgitation (AR) and mitral valve prolapse (MVP) are specifically associated with Down's syndrome, or occur in a comparably retarded population without Down's syndrome. The 92 control subjects resided at the same institution as the 131 cases, and had mental retardation attributable to low birth weight or perinatal asphyxia. Mean (+/- SD) ages of the cases and the control group were 41 +/- 11 years compared with 40 +/- 13 years, respectively. The relative risk of AR among the cases (those with Down's syndrome) was 2.9 (95% confidence interval, 0.65-13.2; P = 0.16) and that of MVP was 3.5 (95% confidence interval, 1.2-10.2; P = 0.02). The results showed that these two valvular abnormalities are specifically associated with Down's syndrome in adults.

Atlantoaxial distance in patients with Down syndrome: standardization of measurement.

Atlantoaxial subluxation is common in persons with Down syndrome. For radiologic screening to be valid, accurate measurement of the atlantoaxial distance (AAD) must be obtained from radiographs of the cervical spine. A radiopaque millimeter scale has been designed to simplify accurate measurement of the AAD from these radiographs.

Etiology of developmental disabilities in Soweto, South Africa.

A retrospective review was undertaken of the records of 725 children who attended the neurodevelopmental clinic at the Baragwanath Hospital in Soweto, South Africa. Most children presented at an early age (less than 2-6 years). The etiological factors were prenatal, 4 per cent; perinatal, 41 per cent; postnatal, 21 per cent. Seventy-one per cent of the perinatal factors were a result of birth related problems in full-term infants; only 22 per cent of this group were represented by premature and low birthweight infants, contrasting sharply with data from industrialized centers. Almost a third of the postnatal causes were a result of acute intracranial infections. Another 13 per cent were a result of the metabolic consequences of acute gastroenteritis. Thus a high proportion of problems were preventable through provision of adequate nutrition, mass immunization campaigns, and adequate primary health care services including antenatal and obstetric management.

Valvular heart disease (aortic regurgitation and mitral valve prolapse) among institutionalized adults with Down's syndrome.

Congenital heart disease has long been recognized in children with Down's syndrome, but little is known about the manifestations of clinical heart disease in adults with this condition. Therefore, 131 adults with Down's syndrome were examined. Clinical heart disease was considered to be present when an abnormally split S2, systolic click, at least grade 3/6 systolic precordial murmur, or any diastolic precordial murmur was heard. Using these criteria, 38 patients had clinical heart disease and 93 did not. To confirm and evaluate the auscultatory findings, echocardiograms were recorded in 37 of the patients. Comparison between patients without clinical heart disease and those with clinical heart disease showed that neither age (39 +/- 11 vs 40 +/- 12 years, respectively) nor gender (60% vs 66% men, respectively) differed significantly. Eleven had clinical and echocardiographic findings consistent with atrial or ventricular septal defect. Findings consistent with aortic regurgitation were identified in 8, and 18 had mitral valve prolapse. These results suggest that in addition to atrial and ventricular septal defect (which have a well recognized association with Down's syndrome), 2 specific, usually asymptomatic, and heretofore unanticipated valvular cardiac abnormalities may be associated with Down's syndrome.

Cardiac surgery for adults with mental retardation. Dilemmas in management.

In summary, cardiac surgery for adults with mental retardation raises a series of controversial legal, economic, ethical, medical, and nursing dilemmas. During the past 20 years, many improvements have taken place in the care of these patients. However, in the future, judicial and statutory mandates requiring high-quality medical care for persons with mental retardation may conflict increasingly with hospital cost-control legislation and thereby affect clinical decisions. For example, it is conceivable that elective repair of an ostium secundum atrial septal defect in an asymptomatic patient will expend the limited resources necessary to carry out emergency revascularization in a symptomatic patient with impending myocardial infarction. This issue becomes even more delicate when the asymptomatic patient is a mentally retarded ward of the state, and the symptomatic patient is a middle-aged man supporting a wife and several college-age children. There may be no easy solution to this problem, and it will provide the grist for many bioethicists. Fortunately, from a practical point of view, we do not currently have to choose between these patients to receive treatment. Our hope is that health care for mentally retarded patients will not be compromised. We believe that decisions about patient management should be based on enlightened clinical judgment rather than on preconceived notions about this population. In the quest for optimal health care delivery, the special needs of these patients should be considered when cardiac catheterization and possible cardiac surgery are contemplated. Although we have presented an approach to a patient with cardiac disease requiring cardiac surgery, we believe that this approach can be utilized for any retarded patient requiring acute medical care. Currently, because there has not been much training in this area, many physicians and nurses lack first-hand experience in caring for the mentally retarded. This inexperience may lead to difficulty in making appropriate decisions. Therefore, we advocate additional exposure in medical and nursing school curricula to the complex health care needs of this population. In conclusion, there appear to be two major issues that pose dilemmas: first, acceptance of the rights of this population to optimal medical management and, second, implementation of appropriate diagnostic and therapeutic strategies.