ities; biotin and zinc serum concentrations were withinnormal limits. At the age of 15 months the patientcontracted a short febrile disease and died at home.

A clinical similarity between cystic fibrosis and type Ipseudohypoaldosteronism, including increased sweatelectrolytes and recurrent lower respiratory tract infec-tions, has been noted by Hanukoglu et al. (3) andMacLaughlin (4). However, patients with type Ipseudohypoaldosteronism may have additional compli-cations (which are infrequent in cystic fibrosis), such asrecurrent ear infections (4) and dermatitis (5).

Since excessivePseudomonascolonization of theskin is not characteristic of cystic fibrosis, despite theelevated sweat electrolytes, additional factors maycontribute to thePseudomonascolonization in patientswith type I pseudohypoaldosteronism. One possibleexplanation is that the NaCl sweat concentration ishigher in some cases of type I pseudohypoaldosteron-ism than in cystic fibrosis.

Pseudomonaswas the dominant pathogen in the skin,ears and conjunctivae in our patient from the first monthof life. The patient had multiple organ insensitivity toaldosterone involving also the sweat glands, as demon-strated by the elevated NaCl concentration in the sweat.This observation may further support the theory that ahigh NaCl concentration predisposes the individual to

the growth ofPseudomonasand the development ofsecondaryPseudomonasinfection.

References1. Marthinsen L, Kornfalt R, Aili M, Andersson D, Westgren U,

Schaedel C. RecurrentPseudomonasbronchopneumonia andother symptoms as in cystic fibrosis in a child with type Ipseudohypoaldosteronism. Acta Paediatr 1998; 87: 472–4

2. Smith JJ, Travis SM, Greenberg EP, Welsh MJ. Cystic fibrosisairway epithelia fail to kill bacteria because of abnormal airwaysurface fluid. Cell 1996; 85: 229–36

3. Hanukoglu A, Bistritzer T, Rakover Y, Mandelberg A. Pseudo-hypoaldosteronism with increased sweat and saliva electrolytevalues and frequent lower respiratory tract infections mimickingcystic fibrosis. J Pediatr 1994; 125: 752–5

4. MacLaughlin E. Pseudohypoaldosteronism and sodium transport.Pediatr Pulmonol 1996; 13 Suppl: 181–2

5. Aberer E, Gebhart W, Mainitz M, Pollak A, Reichel G,Scheibenreiter S. Sweat glands in pseudohypoaldosteronism.Hautarzt 1987; 38: 484–7

B-Z Garty, Department of Pediatrics, Schneider Children’s MedicalCenter of Israel, Petah Tiqva 49202, Israel

ÐÐÐÐÐÐÐÐÐÐÐÐ

Congenital heart disease and parental consanguinity in South India

Sir,Congenital heart disease (CHD) is one of the commonercardiac lesions affecting children throughout the world.Its aetiology is thought to be multifactorial with genetic(chromosomal and rarely monogenic inheritance) andenvironmental factors (maternal rubella, alcohol abuse,diabetes mellitus and drug ingestion) interacting. Con-

sanguineous marriages are reported to be associatedwith an increased incidence of neural tube defects in theoffspring (1), although evidence for a link betweenparental consanguinity and CHD is more controversial(1–4). We report an association between CHD andparental consanguinity in a rural part of South India,with a high rate of consanguineous marriages.

Table 1.Parental consanguinity in the CHD subtypes.

Atrial septaldefects(ASD)

Ventricularseptal defects

(VSD)

Tetralogy ofFallot(TOF)

Patent ductusarteriosus

(PDA)

Pulmonarystenosis

(PS)Multiple

CHD

No. (% total of CHD group) 67 (23%) 64 (22%) 44 (15%) 31 (11%) 14 (5%) 58 (20%)Age (mean� SEM) 21.7� 2 8.4� 1 8.1� 1 10.4� 2 13.6� 3 9.6� 1Parental consanguinity:

No. (% sample) 18 (27%) 21 (33%) 17 (39%) 9 (29%) 7 (50%) 13 (22%)Odds ratio **2.6 ***3.4 ***4.4 *2.9 ***7.0 2.0(95% CI) (1.3–5.1) (1.7–6.7) (2.1–9.3) (1.2–9.3) (2.3–21.7) (0.9–4.2)

*p< 0.05; **p< 0.01; ***p< 0.001, versus control group (n = 192; 12.5% parental consanguinity) (chi-squared test with Yates correction).

ACTA PÆDIATR 88 (1999) Correspondence section 473

The study was carried out in the outpatient clinics ofthe Cardiothoracic and Vascular Surgical Department,which provides free medical care. Two-hundred-and-eighty-nine consecutive cases of CHD were diagnosed,using 2-dimensional echocardiography (ECHO) andDoppler colour flow mapping. A control group of 192consecutive patients were also chosen who had noevidence of CHD on ECHO (76% rheumatic heartdisease; 18% non-cardiac chest pain; 6% respiratory).

Most cases (98%) of CHD were symptomatic atpresentation and 18% were cyanotic. The majority ofpatients in the CHD group were diagnosed to have,atrial septal defect (ASD = 23%), ventricular septaldefect (VSD = 22%), multiple CHD (20%), tetralogy ofFallot (TOF = 15%) and patent ductus arteriosus(PDA = 11%) (Table). Smaller number presented withpulmonary stenosis (PS = 5%), A-V canal defects (2%),transposition of great arteries (1%), coarctation of aorta(0.7%) and anomalous pulmonary venous drainage(0.3%).

Parental consanguinity was noted in 24 (12.5%) ofthe control group compared to 90 (31.1%) of the CHDgroup (odds ratio = 3.2; 95% confidence interval(CI) = 2.0–5.6;p< 0.0001). The rate of parental con-sanguinity was increased in most subtypes of CHDcompared to the control group and there was nosignificant difference in the rate of parental consangui-nity between the CHD subtypes (Table). Overall, therisk of CHD in the offspring was increased in firstcousin (odds ratio = 3.9; 95% CI = 1.9–7.9;p< 0.0001)and uncle–niece marriages (odds ratio = 2.8; 95%CI = 1.3–5.8;p< 0.0001), but not in marriages amongmore distant relatives (odds ratio = 1.9; 95% CI = 0.6–6.28;p = 0.3).

The majority of the CHD patients seen in this studywere symptomatic and presented at a much older agethan would be seen in more developed nations. Thismay be anticipated in a developing nation such as India,where adequate antenatal and postnatal ultrasoundscreening for CHD is not accessible and/or affordableto the majority. Consequently, many congenital anoma-lies, including CHD, are usually detected at a relativelyadvanced stage.

The relatively high rate of parental consanguinitynoted in the control group is consistent with previous

reports from India (3, 4). The rate of parental con-sanguinity among patients with CHD was even greater(31.1%) and apparent with most common types of CHD.This observation partly supports a genetic aetiology forCHD, which may be the result of the expression ofrecessive genes. Although the large World HealthOrganization study (1) did not show an associationbetween CHD and consanguinity, others have reported a1.8–3.6-fold increase in CHD in the offspring ofconsanguineous marriages (2–4). The reason for thisdiscrepancy is not clear, but it may be due partly to thefailure to routinely diagnose CHD by ECHO (1).Moreover, in India, the majority of children withCHD remain undetected (up to 70%) and may also beasymptomatic (approx. 40%) (6). This emphasizes theneed to detect asymptomatic cases of CHD in thecontrol group by ECHO. Unlike previous reports, in thepresent study, patients in both the CHD and controlgroups had undergone ECHO.

References1. Stevenson AC, Johnston HA, Stewart MIP, Golding DR.

Congenital malformations—a report of a study of consecutivebirths in 24 centres. Bull W H O 1966; 34 Suppl

2. Badaruddoza A, Akhtaruzzaman M. Inbreeding and congenitalheart diseases in a North Indian population. Clin Genet 1994; 45:288–91

3. Gev D, Roguin N, Freundlich E. Consanguinity and congenitalheart disease in the rural Arab population in northern Israel. HumHered 1986; 36: 213–7

4. Vishnupriya S, Ahuja YR, Reddy YR, Reddy GD, Rao VS, RaoPN. Inbreeding, mortality and genetic load in families withcongenital heart diseases. Acta Anthropogenet 1981; 5: 151–5

5. Naderi S. Congenital abnormalities in newborns of consanguin-eous and nonconsanguineous parents. Obstet Gynaecol 1979; 53:195–9

6. Vashishtha VM, Kalra A, Kalra K, Jain VK. Prevalence ofcongenital heart disease in school children. Indian Paediatr 1993;30: 1337–40

MG Gnanalingham1, KK Gnanalingham2 and A Singh2, Departmentof Paediatrics1, Booth Hall Children’s Hospital, Charlestown Road,Blakley, Manchester, M9 7AA, UK; Department of Cardiothoracicand Vascular Surgery2, Sri Sathya Sai Institute of Higher MedicalSciences (SSSIHMS), Prashanthi Gram Anantapur District, PIN:515134, A.P. India

474 Correspondence Section ACTA PÆDIATR 88 (1999)