Congenital adrenal hyperplasia: should nationwide screening be implemented in Thailand?

A project to establish the Thailand National Neonatal Screening Program was started in 1996 with the objective of screening every newborn for congenital hypothyroidism and phenylketonuria. Over a million newborns were screened and over 430 abnormal cases were detected. A study was also conducted to determine the feasibility of including CAH screening in the program. The incidence of this disease has not yet been clearly determined. Since 1999, 58,563 newborns have been screened for CAH and 144 newborns with serum 17-OHP higher than 40 ng/mL were recalled for confirmatory tests. Of those, 68 were retested and 6 were found to have elevated 17-OHP levels. Two were confirmed with salt wasting CAH one month after birth, two others were diagnosed with another disease that caused electrolyte imbalance, one patient died, and the sixth required further clinical diagnosis. Five other babies were reported dead before the second specimens could be collected for confirmation. It appears that CAH may be one of the underlying causes of death among Thai newborns and the incidence may be higher than thus far shown due to incomplete confirmation of positive screens and deaths to some infants.

Neonatal screening program in Thailand.

The Neonatal Screening Program for congenital hypothyroidism (CHT) and phenylketonuria (PKU) commenced in 1996 with the objective of bringing better quality of life to people throughout the country, especially in the remote areas. This involved the implementation of routine services to the public health infrastructure all over the country. The plan of action has been designed so that by the year 2000 all public health service units throughout the country may provide screening services which can cover 1.2 million babies/ annum. Implementation of the screening program has been performed through public health sectors all over the country. These involved: education of the health personnel and communities, implementation of routine specimens collection and delivery systems to the central laboratories, establishment of central laboratory screening services, routine follow up and case management. Local in-house reagents using ELISA and IRMA techniques have been developed and utilized as screening and confirmation tests for CHT. In addition, Guthrie's test has been used for PKU screening and the automated Fluorometry has been selected for PKU confirmation. All 724 community hospitals have provided newborn screening services as one of the basic requirements for newborns according to public health policy. Of 1,425,025 babies screened, 3,450 (0.24%) were above the first screening cut off for CHT (TSH > 25 mU/l) and 321 (0.02%) for PKU (PKU > 4mg/dl). With a 63.10% follow up rate, the incidences were 1:3,314 for CHT and 1:237,504 for PKU. Newborn screening has been implemented as routine practice for all public health sectors of the country for CHT and PKU. It is expected that by the year 2003, all Thai newborns will be provided with screening services resulting in a better quality of life for the next generation.