The congenitally deaf infant who acquires deafness prior to development of language present special problems when compared to other hearing impaired individuals. This is because both the development of speech and of language depends on adequate hearing. As speech and language are our prime means of communication, the congenitally deaf child is automatically also handicapped in his psychological development, social adaptation and work adaptability. The authors reviewed cases of congenital hearing loss presenting on a 20 year period to establish the incidence of congenital hearing impairment in the Maltese islands; to determine the common causes; to highlight any difficulties in early diagnosis and management of these children.peer-reviewe

Degiorgio, Raymond

Fenech, Anthony G.

Pace Balzan, Jacqueline

Saliba, F.

English

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Maltese Medical Journal 51 Volume IT Issue II '90/91 CONGENITAL HEARING LOSS IN MALTA A SURVEY 1. Pace Balzan, A. Fenech, F. Saliba, R. Degiorgio The congenitally deaf infant who acquires deafness prior to development of language present ~;pccial problems when compared to other hearing impaired indivudals. 'This is because both the development of speech and of language depend on adequate hearing. As ~1JCech ,md language are our prime means of communication, the congenitally deaf child is automatically also handicapped in his psychological development, social adaptation and work adaptability, A deaf child's environment is limited to visual ,md tactile stimulation. He misses the comforting sound" of his mother;'s voice, the naunces of speech, He misunderstands and his reactions arc often misunderstood, This might result in emotional and behavioural problems. In short a deaf child is faced by a multiplicity 01' problems. Hearing loss is not an obvious handicap and is often missed because it is mm;ked by the emotional and other problems complicating iL Early diagnosis of hearing impairment is critical to enable efforts to Ix: made to help tIlis child make full use of what hearing he ha'>, The totally deaf child will develop no ~-pccch or language unless exp.:rtly helped. The partially deaf child will show retardation of speech and of language development, which will remain faulty. The average incidence of congenital hearing loss in European countries is between 2 to 3 per 1,000 births, a very small numlx:r of cases, which renders identification and early diagnosis even more difficult unless a s1JCCial effort is made in this direction, With these facts in mind and a<; part of a projected wider study, we reviewed ~s of congenital hearing loss presenting on a 20 year period, Our main aims were: 1) to establish the incidence of congenital hearing impajnnent in the Maltese islands; 2) to determine the common causes; 3) to highlight any difficulties in early diagnosis and management of these children; 1. INCIDENCE TABLE 1 No. of 10 cases 9 8 7 6 5 4 3 2 o A total of 64 cases were collected over a period between 1970- 1989. Another 4 cases were added although diagnosed in 1958 and 1964 re~,;pectively. This is probably not a complete figure for a number of rea<;ons mainly because of people seeking treatment elsewhere, emigration, etc., but classification of these cases on illl annual basis would appear to show an average of 3 new cases diagnosed per year with the exception of the years 1977, 1979 and 1985. The increase over these years coincided with rubella epidemics. 1958 '64 '70 '71 '72 '73 '74 '75 '76 '77 '78 '79 '8081 '82 '83 '84 '85 '86 '87 '88 Years of Incidence 2. AETIOUXN All cases were classified as shown in Table n. TIle major cause of prenatal hearing loss would app.:ar to be viral disc.'lses with rubella responsible in 25 cases (33%). There was one case of cytomegalovirus infection, one cach of mca<;les and inlluenza and 2 of 'pyrexia of unknown origin.' This category should . therefore all but clisappe<rr following the national immunisation campaib'11 against Rubella. In four patients there was a llistory of pre­eclamptic toxaemia, in 2 threatened J. PACE BALZA:\ MD FRCS CONSULTANf A. FEl'<'F£H MD SlIO F. SALmA AUDIOLOGISf R. DEGIORGIO SPEECH 171ERN'ISf ENT DEPAR1MENT, DNlSION OF SURGERY, sr. WKE'S HOSPrfAL Maltese Medical Journal 52 Volume IT Issue IT '90/ 91 abortion and there was one case of a clm;sified as premature birth or of low diabetic mother giving birth to a deaf birth weight, this being 2 to 3 kg or less. child. Twenty two cases suffered some fonn of There W£L<; a strong family history in 14 of nconatal jaundice the severity of which the C£L<;CS in the fonn of a specific hearing could not be detennined. Two cases loss, poor speech and language required exchange transfusion, one of development, and/or delay in which was secondary to Rhesus development of speech. Of these, 2 cases incompatibility. Birth tmuma with anoxia were cla<;sified as specific syndromes. accounted for 10 cases (13%). The usc of drugs in pregnancy as a possible Taking into consideration the annual birth eause of hearing loss was Limited to 4 rate, it would appear that management cases. The drugs involved were salicylates during pregnancy and delivery account in 2 cases, non-steroidal anti­ for a minuscule percentage of cames of inflammatory drugs in one case and anti­ hearing loss. histamines in another. The post-natal group have 3 cases One woman was exposed to X-rays at secondary to the exanthemata (scarlet four months gestation and another fever, mca<;les and mumps encephalitis); underwent surgery under general one followed routine vaccination; 2 febrile anaesthesia at 12 weeks p[pregnancy. convulsions the cause of which is Twenty four cases (30%) could be unknown and their significance doubtful; TABLE IT CAUSES OF HEARING LOSS I. 	 PRENATAL A. 	 Genetic 1. Strong Family History 12 2. Specific Syndrome 	 2 B. 	 Non Genetic 1. Diseases during Pregnancy a. Rubella 	 25 b. 	 Other Viruses 1 measles 2 influenza c. Others 	 2 PHO. B. Toxaemia 	 5 cases C. Maternal diabetes 	 1 case D. Nephritis 	 Nil E. Threatened Abortion 	 2 cases 11. 	 Drugs During Pregnancy 4 cases (2 salicylates, 1 Non Steroidal antiflammatory, 1 antihistamine) Ill. Other 	 2 cases: 1 had general anaesthesia during pregnancy; 1 underwent X-Ray Examination 11. 	 PERI-NATAL 1. Prematurity 	 24 cases 2. 	 Haemolytic disease of the new born 22 cases (2 required exchange transfusion). 3 . Birth trauma - anoxia o cases Ill. POSTNATAL A. 	 Genetic possibly 1 case B. 	 Non-genetic a. 	 Infectious diseases: scarlet fever; 1 measles; 1 mumps encephalitis; 1 post vaccination; 3 meningitis; 3 febrile convulsion b. 	 Trauma: 2 cases of head injury c. 	 Ototoxic drugs: 2 cases (gentamycin) IV 	 IDIOPATHIC 4 Cases 3 on meningitis, 2 of whom also received ototoxic drugs (gentamycin). Two cases followed severe head injury. Only 4 eases fell into the "idiopathic" group, i.e. about 8%. This would appear to be considerably lower than expected by other authors (1,2) and this possibly because of our smaller numbers. It is moreover envisaged that with better understanding of genetic caLL<;CS this group will fall still further. 3. 	 AGE AT DIAGNOSIS It has long been established that early diagnosis and management of deafuess is of the utmost importance (3). The ideal should be not later than 18 months. Dial:,'Tlosing early deafness is not simple and as a recent EEC study (4) showed 90% of cases had not been diagnosed by the first birthday, and as many as 50% were still not diagnosed by the age of three. 50% of our cases were diai:,lJ1osed in or around the 1st year of life, 25% between 2 and 3 years and 25% beyond the 3rd year. (Table 3). It would appear at first hand therefore, that we are not doing too badly at the early diagnosis of this handicap. This could be explained by the centralisation of medical facilities at our Hospital and by adequate awareness of the problem in both the medical and teaching professions. Closer examination, however, does not show any place for complacency in this respect Of the 68 cases considered, only 4 fell in the idiopathic group. Sixty four cases were in the so-called 'at risk' category and with the proper co-ordination of services should have been picked up at an even earlier stage. The case of Waardenberg SYndrome was only diagnosed at the age of 4 years when she at first attended school; one child with cerebral palsy at 3 1/2 years; one with monoplegia and epileptic seizures at 3 years; another who required an exchange transfmion for Rh incompatibility wa diagnosed at 6 years of age. The great majority of cases were self-referrals usually because the parents' attention was drawn to the child's apparent apathy and non-response to sound and because of poor speech development In many cases this hearing loss was overshadowed by more obviom handicaps and missed for years though the child was under medical supervision. Maltese Medical Journal 54 Volume IT Issue II '90/91 TABLE ID AGE AT DIAGNOSIS 4. MANAGEMENT We were mostly concerned with:­a) The age at which the child was fitted with a hearing aid; b) The time interval between diagnosis and supply of the aid; c) What other help, if any, was given in the way of speech therapy by peripatetic teachers, use of apparatus etc. Table IV shows the age at which the child was fitted with a hearing aid Of the 33 patients diagnosed in the first year of life, only 8 had been fitted with a hearing aid at the age of one year. Another 7 had been fitted by the age of 18 months and 5 within 2 years. More than half of our patients were therefore supplied with a hearing aid at too late a stage in their development for them to obtain maximum benefit This is not to be taken as showing the service offered in a bad light Many of these cases were diagnosed late, while others fell victims to parents' mistaken and misguided decisions. The normal reaction of these parents ranged from initial shock, denial, anger (often at the clinician and the team trying to help) and ultimate «<eptance - a time consuming process, during which the child languishes without his hearing aid in a silent world and during which his language and emotional development remain stunted. Around 50% of patients received their hearing aids within 6 months of diagnosis, 15% within 12 months, another 13% within 18 months and another 15% within 2 years or more. (Table 5) Again the reasons mentioned aOOve may be playing a part. It does seem a pity however that 20 patients diagnosed before the age of 2 years all ended up being fitted with a hearing aid well after the age of 2 years. When one considers the importance of introducing sound to the child's consciousness as early as possible in life if he is to stand any chance in developing speech and language one can understand that one month (let alone six) is too long. Out of a total of 68 children, 19 received speech therapy while 49 did not (Table 6). Out of 19 who received speech therapy, 8 suffered from moderate to severe hearing loss and could expect some benefit from speech therapy while the other 11 suffered from severe to profound hearing loss and were correspondingly less likely to benefit from simple speech therapy. Of the 49 children not receiving speech therapy, one suffered from mild hearing loss and probably required no therapy, while 13 suffered from moderate to severe hearing loss missed out on this form of help. It would appear that referral for speech therapy was haphazard and often the initiative to contact the speech therapist was taken by the parents themselves. In contrast the great majority enjoyed the help of a peripatetic teacher in varying periods of one to two hours per week. None of the children attending for speech therapy wore special aids. 5. EARLY DIAGNOSIS The problem of congenital hearing loss is not a large one in numerical terms even when contrasted with the more widespread problem of acquired hearing loss in the general population. It consists basically in isolating 3 deaf individuals from an annual group of 5,000 live births. Various methods have been tried but none are fool-proof. i) Screening Programmes: are available in many European countries. The aim is to identify the hearing impaired some time in the first year. This is supplemented by pre-school screening in an attempt to further 'close the net'. Results have not lived up to expectations and an EEC study (5) showed only 55% of children with a loss of 50 dB or more were identified before the age of 3. In a hospital-based obstetric service such as ours, nw-natal screening is a possibility provided an effective method is available. There are problems however:­a) It has been estimated that screening on neo-nates using the auditory response cradle in an area with a live birth rate of 3,000 annually required a full time staff of three at an estimated cost of Lm3,000 to Lm6,000 per case (6). Each case ~. . Maltese Medical Journal 55 Volume IT Issue IT INTERVAL BElWEEN DIAGNOSIS AND FrTTlNG OF HEARING AID .........................:...:.:.:.:.:.:.:.:.:.:.:.:.:i identified would then have to be further investigated by electrophysiological means, behavioural studies etc. What is just as important is the availability for the rehabilitation of these infants. Fitting of hearing aids in neo-nates requires even more skill and experience than the fitting of an older child. Unless these facilities are available, neo-natal screening doe not appear to be a viable proposition. b) The "at risk" register - Many (7 and 8), have expressed doubts as to the usefulness of such registers which are generally accepted as being incomplete. However in a small country like ours and especially with its now mainly hospital-based obstetric services, this method could be advantageous. From the survey carried out it appears that 95% of cases would have been immediately identified had an 'at risk' register existed. This would of course require the co-operation of the Paediatric and Obstetric Departments but that should not prove too difficult to obtain. c) Education:- Educating the general public and parents in particular about the possibility of deafness in their offspring should prove helpful and especially useful in a small country like Malta. More than 90% of the cases in our survey were self­referred on the basis of parental suspicion of hearing loss. TABLE VI CHILDREN RECEIVING Receiving Speech Therapy 6. REHABILITATION Rehabilitation of a congenitally deaf child is a complex problem involving not only the child and his parents but also their progressive relations with a group of professionals together with the interactions between these groups of people. The present situation is not exactly an ideal one. The child and his parents find themselves shuttled between one department and another where different people offer differing or even conflicting opinions and advice. The only beacons of stability for these people in these Islands have been the lay associations for the deaf which have provided sterling services on an emotional and information level. The recent introduction of 'Case Conferences' is a possible step in the right direction but there is no doubt that further development of the Audiology Unit at St Luke's Hospital together with more centralisation and greater participation of the Department of Speech Therapy wolking hand in hand with the Department of Paediatrics and Neonatology is the answer. The involvement of the Department of Education as this stage would involve '90f91 home visits by peripatetic teachers but the process of rehabilitation should be soundly established by the time the child rea:hed school age. REFERENCES (1) FRASER GR. 1964 RESEARCH IN DFAFNESS IN CIl/WREN, OXFORD BLACKWF1.L (2) MARAN A.GD. TIlE CAUSES OF DEAFNESS IN CHllDREN 1966, J . LARYNG AND om, 80,495. (3) £WING '57 SCREENING TESlS AND GUIDANCE CUNICS FOR BARn:s AND YOUNG CHlWREN IN "EDUCATIONAL GUIDANCE AND TIlE DEAF CHIlD PAGES 2143. (4) MARTIN, JAM. DIAGNOSIS AND COMMUNICATNE ARllllY IN DFAF Cfl/WREN IN mE EUROPEAN COMMUNflY. AUDIOWGY 1982, 2/, 185-196. (5) MARTIN JAM AND MOORE WJ. 1979 CHI[J)HOOD DEAFNESS IN THE EUROPEAN COMMUNI1Y EUR 6413 LUXEMBOURG; COMMISSION OF mE EUROPEAN COMMUNrFIES. (6) HALL D.M. & GARNER J. FEASARILlTY OF SCREENING AlL NEONATES FOR IlEARING WSS. ARCH. DISEASES CJ/lW. 1988, 63 (6) 652-53. (7) PARVING J. EARLY DETECTION AND IDENTIFICATION OF CONGENITAUEARLY ACQUIRED IlEARING DISARllllY. WHO TAKES TIlE INITIATNE. INIERNATION JOURNAL OF PAEDIA7RIC OTORHINOLARYNCJOWGY, 1984, 7, 107-117. (8) RIKO, K., HYDE, ML., AND ALBERTI, PW. (/985) HEARING WSS IN EARLY INFANCY; INCIDENCE, DETECTION AND ASSESSMENT. THE LARYNGOSCOPE, 1985, 95, 137-145 SPEECH THERAPY IN RELATION TO SEVERITY OF HEARING LOSS 8 cases Mooerate to Severe hearing bss 11 cases Severe to Profound hearing bss Not ReceMng Speech Therapy hearing No S. lherapf 13 11 The copyright of this article belongs to the Editorial Board of the Malta Medical Journal. The Malta Medical Journal’s rights in respect of this work are as defined by the Copyright Act (Chapter 415) of the Laws of Malta or as modified by any successive legislation. Users may access this full-text article and can make use of the information contained in accordance with the Copyright Act provided that the author must be properly acknowledged.  Further distribution or reproduction in any format is prohibited without the prior permission of the copyright holder. This article has been reproduced with the authorization of the editor of the Malta Medical Journal (Ref. No 000001)  

cases Mooerate to Severe hearing bss 11 cases Severe to Profound hearing bss Not ReceMng Speech Therapy hearing

Congenital hearing loss in Malta : a survey

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Congenital hearing loss in Malta : a survey

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