404 THE EAR vii. Alporfs syndrome is found mainly in boys in whom a progressive glomerulonephritis is associated with deafness. viii. Refsurrfs syndrome which consists of ichthyosis, ataxia, retinitis pigmentosa, night blindness, mental retardation and a perceptive hearing loss. B. Endemic congenital deaf-mutism is associated with goitre and cretinism." The pathological changes mainly affect the middle ear and the window niches become narrowed or occluded and the stapes more or less immobile. In many' cases, however, deaf-mutism probably depends mainly on the poor mental development of the child. C. Maternal rubella. Children born of mothers who have suffered from rubella during the first 3 months of pregnancy have a 35 per cent chance of being born deaf and may also have heart defects, cataract and dental abnor- malities. Other virus illnesses in the first trimester, e.g. glandular fever and influenza, may have a similar effect. D. Other maternal diseases have been blamed for deafness in the baby, e.g. measles, nephritis, diabetes and syphilis. E. Drugs taken during pregnancy. The results of thalidomide are now well known but deafness has also been attributed to the mother being treated with streptomycin and quinine. 2. PERINATAL CAUSES Prematurity, dysmaturity, birth injuries, anoxia during delivery, prolonged labour and especially hyperbilirubinaemia can cause deafness. 3. POSTNATAL CAUSES Deafness in early infancy is mainly due to infection, e.g. meningitisdue to meningococcus, pneumococcus or tuberculosismeasles, mumps, influenza, etc. It may be also due to treatment of infections by drugs such as strepto- mycin, neomycin or kanamycin. DIAGNOSIS OF CONGENITAL DEAFNESS. If a deaf child is to make the best use of its residual hearing, if it is to learn to speak well and if it is going to benefit from education the diagnosis must be made at as early a stage as possible so that suitable treatment and education may be commenced early enough. Where any of the causative factors exist during pregnancy, at the time of delivery or if illnesses which might cause deafness occur in infancy the possibility of deafness must be excluded. This will require screening tests by doctors or health visitors, which may have to be repeated on several occasions until deafness can be eliminated with certainty in those 'At Risk' children. Deafness may be suspected by the parents who notice that their baby does not respond to sound. This suspicion must be treated seriously and hearing tests applied until there is no doubt that the hearing is normal. Unfortunately, in many cases still, deafness is not suspected until there is delay in the develop- ment of speech. In these cases also the hearing must be thoroughly and accurately tested. Whenever deafness is suspected a careful history must be taken and this will include the antenatal history as well as the nature of the confinement and postnatal health.