Autosomal recessive chronic granulomatous disease presenting with cutaneous dermatoses and ocular infection.

Dermatoses such as eczematous dermatitis and cutaneous infection are recognized presentations of primary immunodeficiency (PID). However, atopic dermatitis affects approximately 10% of infants, and cutaneous infections are not uncommon in children, therefore the challenge for the dermatologist is to distinguish the few patients that have PID from the many that do not. We report on a 6-year-old girl who was ultimately diagnosed with autosomal recessive chronic granulomatous disease (AR-CGD) after presenting to various hospitals with dermatitis, scalp plaques recalcitrant to treatment, and recurrent infections over a 3-year period, and describe some aspects of her diagnosis and management. This report highlights the importance of considering rare disorders such as AR-CGD in the differential diagnosis of recurrent or recalcitrant dermatological infections in children.

Biochemical and molecular characterization of tyrosine hydroxylase deficiency in Hong Kong Chinese.

Tyrosine hydroxylase deficiency is a rare neurotransmitter disorder affecting the rate-limiting step in catecholamine biosynthesis. There are about 40 cases reported worldwide. Here, we report the biochemical and molecular findings of eight unrelated Chinese patients with tyrosine hydroxylase deficiency. We have identified eight novel mutations with 5 missense, 2 nonsense and 1 splicing mutations in the TH gene, namely p.R153X, p.R169X, p.G294R, p.G315S, p.A385V, p.I394T, p.G408R, and c.1163+5G>C. The mutations of the TH gene in Chinese are heterogeneous.

Acute syphilitic posterior placoid chorioretinitis in late latent syphilis.

Diverse manifestations of ocular syphilis may involve any structure in the eye, at any stage of the disease. Posterior uveitis in the form of posterior placoid chorioretinitis has been described in secondary- and tertiary-acquired syphilis. In this case report, we present a 47-year-old man with late latent syphilitic infection and fundoscopic, as well as angiographic findings consistent with acute syphilitic posterior placoid chorioretinitis. To our knowledge this form of patchy multifocal choroiditis has never been described in the latent stage of the disease.

Complete recovery from acute encephalopathy of late-onset ornithine transcarbamylase deficiency in a 3-year-old boy.

Ornithine transcarbamylase deficiency is the commonest urea cycle disorder which is transmitted in X-linked inheritance. It is mainly characterized in males by acute encephalopathy and hyperammonaemia with fatal outcomes in both classical neonatal and late-onset types. We report a 3-year-old healthy Hong Kong Chinese boy who presented with acute encephalopathy and coma after three days of gastroenteritis. He had no focal neurological deficit and brain CT imaging was normal. His plasma ammonia (54 micromol/L) and glutamine (747 micromol/L) concentrations were normal. The only biochemical abnormalities detected were marked orotic aciduria (700 micromol/mmol creatinine) and elevated urinary uracil. He regained consciousness spontaneously after three days under intensive care with parenteral fluid therapy. He recovered completely without any neurological deficits. Five months after discharge, urinary uracil concentration remained elevated despite normalized orotic acid concentration. Finally, ornithine transcarbamylase deficiency was diagnosed by DNA analysis. A missense mutation of arginine-to-glutamine substitution on amino acid 277 (p.R277Q) was revealed to be a late-onset mutant. Our case strengthens the argument that in any child with coma or acute encephalopathy of undetermined cause, genetic analysis of the OTC gene and the measurement of urinary uracil concentration remain the most reliable indicators of late-onset OTCD during acute and even quiescent phases. Existing neonatal screening programmes for inheritable metabolic disorders fail to detect late-onset variants. Therefore, a high clinical suspicion is a key to correct and timely diagnosis, especially in those patients with atypical presentations.

Phaeochromocytoma in children.

Phaeochromocytoma is a rare disease in childhood with a subtle and wide range of clinical presentations. We report two confirmed cases and one potential case of phaeochromocytoma, each belonging to a different disease spectrum or syndromal disorder, namely sporadic phaeochromocytoma, von Hippel-Lindau disease, and multiple endocrine neoplasia type 2a. Knowledge of the molecular basis of the condition helps to make the diagnosis. Affected individuals and their family members should be screened for any associated syndromal disorders that can carry a substantial degree of morbidity and mortality.

The effect of pregnancy on thyroid nodule formation.

Epidemiology data have revealed a higher prevalence of nodular goiters in women than men in both iodine-sufficient and iodine-deficient areas. Increased prevalence of thyroid nodules has also been reported in women with higher gravidity. However, the association between pregnancy and thyroid nodule formation has never been studied. The aim of our study was to evaluate the incidence of thyroid nodules during pregnancy and determine whether pregnancy will induce thyroid nodule formation. Two hundred twenty-one healthy southern Chinese women in the first trimester of their pregnancy were studied prospectively. Thyroid ultrasonography, thyroid function tests, and urinary iodine excretion were measured at first, second, and third trimesters of pregnancy as well as 6 wk and 3 months postpartum. Thyroid nodules (>2 mm in any dimension on ultrasonography) were detected in 34 (15.3%) subjects at first trimester, with 12 (5.4%) subjects having more than one nodule. Eight subjects had clinically palpable nodules. Women with thyroid nodules were older (P < 0.01) and had higher gravidity (P < 0.02) than those women without thyroid nodules. The volume of the single/dominant nodules increased from 60 (14--344) mm(3), median (interquartile range) at first trimester to 65 (26-472) mm(3) at third trimester (P < 0.02). These nodules remained enlarged at 103 (25-461) mm(3) 6 wk postpartum (P < 0.005) and 73 (22-344) mm(3) at 3 months postpartum (P < 0.05). Patients with thyroid nodules had lower serum TSH values (P < 0.03) and higher Tg levels (P < 0.05) throughout pregnancy. Appearance of new nodules was detected in 25 (11.3%) women as pregnancy advanced so that by 3 months postpartum, the incidence of thyroid nodular disease was 24.4% (P < 0.02 vs. first trimester). Compared with those with no detectable nodules throughout pregnancy, subjects with new nodule formation had higher urinary iodine excretion from second trimester onward (P all < 0.05). However, no difference could be detected in their TSH and Tg levels throughout pregnancy. Fine-needle aspiration on nodules greater than 5 mm in any dimension after delivery (n = 21) confirmed the majority having histological features consistent with nodular hyperplasia. No thyroid malignancy was detected. In conclusion, pregnancy is associated with an increase in the size of preexisting thyroid nodules as well as new thyroid nodule formation. This may predispose to multinodular goiter in later life.

Onset of significant GH dependence of serum IGF-I and IGF-binding protein 3 concentrations in early life.

Forty-eight normal full-term Chinese babies (25 boys and 23 girls) were followed up every 2 mo in the first year and every 3 mo during the second year of life for anthropometric measurements. Blood samples were taken at birth and at 6, 10, 12, and 18 mo after birth for serum GH-binding protein, IGF-I, and IGF-binding protein 3 analysis. Onset of the childhood phase of growth in the infants was determined from the growth data plotted on Infancy-Childhood-Puberty growth charts. The serum GH-binding protein concentrations were low in cord blood but rose significantly at 6 mo, with slower rises in late infancy and early childhood. However, a significant rise in serum IGF-I and IGF-binding protein 3 levels was only observed from 10 mo of life onward. The change in IGF-I between birth and 6 mo was significantly correlated with length gain (r(2) = 0.35, p < 0.05) and body mass index gain (r(2) = 0.41, p < 0.01) during the same period. The 34 infants with onset of childhood phase of growth between 6 and 10 mo had a higher mean serum IGF-I value at 10 mo (8.8 +/- 5.8 nM versus 4.9 +/- 3.1 nM; p < 0.05) and higher length velocity between 10 and 12 mo (16.3 +/- 4.7 cm/y versus 8.8 +/- 4.3 cm/y; p < 0.001) compared with the 14 infants with a later onset after 10 mo of age. A significant correlation between a change in serum IGF-I and IGF-binding protein 3 levels was observed during the three 6-mo periods between birth and 18 mo, but a significant correlation between a change in serum GH-binding protein and a change in serum IGF-I or IGF-binding protein 3 levels was only seen between 12 and 18 mo of age. The multiple regression analysis (r(2) = 0.43, p = 0.0002) revealed that the change in serum GH-binding protein and IGF-I concentrations between 6 and 12 mo of age and the age of onset of childhood phase of growth could explain 43% of the length gain between 6 and 12 mo of age in our babies. The results of our study support the hypothesis that the onset of the childhood phase of growth is associated with the onset of significant GH action on growth.

Critical growth phases for adult shortness in Hong Kong Chinese.

OBJECTIVES: This study was designed to explore whether the influence of subnormal growth in fetal, infancy, childhood and pubertal phases on adult short stature was the same when comparing privileged and underprivileged populations. METHODS: Data came from two longitudinal growth studies: 1) Hong Kong Chinese children who were born in 1967 (n = 132), and 2) the comparatively more privileged Swedish children who were born in 1973-1975 (n = 2,850). RESULTS: 68% of Hong Kong Chinese children had two or more growth phases subnormal, much higher than the 12.4% for Swedish children. 42.4% of Hong Kong Chinese were short at final height, much higher than the 2.2% for Swedish children. Subnormal growth in any growth phase was associated with an increased risk of adult short stature in both series (p<0.01). After adjustment for mid-parental height, the place of residence (Hong Kong/Sweden) was not significant for adult shortness (p>0.05) in the pooled data. CONCLUSIONS: The impact of subnormal growth in any phase on adult shortness is similar in privileged and underprivileged populations. The much higher prevalence of subnormal growth and consequently adult short stature in developing countries is likely mainly attributable to adverse extrinsic or environmental influences.

Mild iodine deficiency and thyroid disorders in Hong Kong.

OBJECTIVES: To review evidence of iodine deficiency and clinical thyroid disorders in Hong Kong. DATA SOURCES: Publications on local dietary iodine intake, the iodine content of local food items, and clinical thyroid problems in the Hong Kong population. DATA EXTRACTION: Data was extracted and evaluated independently by the authors. DATA SYNTHESIS: Iodine is an essential nutrient. Iodine deficiency can lead to goitre, hypothyroidism, mental deficiency, and impaired growth. It is now appreciated that determination of goitre incidence in children alone may grossly underestimate the problem of iodine deficiency in a population. In total, the evidence indicates that iodine deficiency exists in Hong Kong, leading to clinical problems of transient neonatal hypothyroidism, goitrogenesis, and thyroid disorders in pregnant women and neonates, as well as thyroid dysfunction in the elderly. CONCLUSION: A supplementation programme aimed at a relatively uniform iodine intake is recommended to avoid deficient or excessive iodine intake in subpopulations.

Ultrasound-guided hydrostatic reduction of childhood intussusception: technique and demonstration.

The authors review the technique of ultrasound-guided hydrostatic reduction of childhood intussusception and illustrate, in real-time fashion, the treatment of three cases with this technique. Two cases of successful reduction of ileocolic intussusception are demonstrated. The third case is an example of the complex fronded appearance of ileo-ileocolic intussusception and failed reduction. This technique is recommended as an alternative method for the treatment of childhood intussusception, as it does not involve ionizing radiation and is a simple and safe procedure.

Pathways from emotional adjustment to glycemic control in youths with diabetes in Hong Kong.

OBJECTIVE: To examine factors that influence emotional adjustment, adherence to diabetic care, and glycemic control in Hong Kong youths with insulin-dependent diabetes mellitus (IDDM). METHODS: Seventy youths, their mothers, and matched controls provided information on health beliefs, authoritarian parenting style, parent-child conflict, emotional adjustment, and adherence to medical regimen. Glycosylated hemoglobin levels were obtained to measure glycemic control. RESULTS: Predictors explained 34% of the variance in emotional adjustment and 39% of the variance in glycemic control. The data supported a pathway from emotional adjustment to self-efficacy to adherence behaviors to glycemic control. In contrast to Western culture and consistent with prediction, parenting style did not associate with negative outcomes, and even relatively low levels of parent-child conflict correlated negatively with emotional adjustment in this culture. CONCLUSIONS: Management of conflict and self-efficacy enhancing interactions are suggested interventions to enhance adherence to diabetic care in Hong Kong youths with IDDM.

The effect of 3 years of recombinant growth hormone therapy on glucose metabolism in short Chinese children with beta-thalassemia major.

Growth retardation and diabetes mellitus are common in children and adolescents with beta-thalassemia major despite hypertransfusion regimen and iron chelation therapy. The purpose of this study was to investigate the effects of growth hormone (GH) treatment on glucose metabolism in children with beta-thalassemia major. GH therapy for 3 years improved the height SD scores of eight short prepubertal Chinese children with beta-thalassemia major from -2.15 +/- 0.90 to -1.14 +/- 0.78 (paired t-test, p = 0.01) without excessive advancement in bone age (ABA/CA = 0.95 +/- 0.27). There was no deleterious effect on glucose metabolism with no change in fasting blood sugar, serum fructosamine, fasting and stimulated insulin to intravenous glucose infusion (sum of 1+3 min insulin, In 1+3'; incremental insulin 0-10 min area above fasting concentrations, deltaInAUC0-10'; ratio of incremental 0-10 min insulin area above fasting concentrations over glucose area above fasting concentrations, delta0-10'AUCIn/G; ratio of incremental 0-10 min insulin over peak glucose above basal 0-10 min, delta0-10'InAUC/deltaGPeak), and glucose disappearance coefficient (Kg). Short term GH therapy improves the height of children with beta-thalassemia major but the effect of treatment on final height still needs to be determined.

Fetal size to final height in Hong Kong Chinese children.

OBJECTIVES: It has been known that size at birth is important for postnatal growth and final height. However, there are few data in the literature on the difference in height growth patterns from fetal size to final height between less privileged and more privileged populations. The aim of this study was to describe the important features in height growth from birth to maturity in an underprivileged Hong Kong Chinese cohort in comparison to a more privileged Swedish cohort. METHODS: The longitudinal height growth data from birth to maturity in full-term healthy Hong Kong Chinese children (n=132) who were born in 1967 were analyzed, and compared with those for Swedish children who were born in 1973-75 (n=3650). RESULTS: Children with longer birth length achieved taller adult stature with respect to their target height. The mean final height retained the same order as that of the mean length at birth for various birth length groups. All children in the Hong Kong Chinese series showed catch-down height growth during the first 2 years of life, in contrast to the catch-up in smaller babies and catch-down in larger babies for the Swedish series. The growth deficit for the Hong Kong Chinese was -0.9 SDS at birth, -1.8 SDS at 2.0 years of age, -2.1 SDS at 8 years of age, and -1.7 SDS at final height. CONCLUSIONS: Fetal size is important for postnatal growth and attained final height with respect to a child's familial genetic potential in stature, not only for privileged populations, but also for underprivileged populations. However, children in underprivileged populations experience a persistent increasing growth deficit during infancy and childhood. Special attention should be given to monitor their growth status in early years and to institute appropriate intervention programs.

Epidemiology of diabetes mellitus in children in Hong Kong: the Hong Kong childhood diabetes register.

OBJECTIVES: To establish a registry for Chinese children with onset of type 1 (insulin dependent) diabetes mellitus before 15 years of age and to determine the incidence of childhood onset type 1 diabetes mellitus in Chinese children in Hong Kong. RESEARCH DESIGN AND METHODS: A registry was established in 1997 to collect childhood diabetes cases retrospectively from all districts in Hong Kong. The study included all newly diagnosed cases of diabetes with onset < 15 yr of age from 1st January 1984 to 31 December 1996. Primary ascertainment was based on review of medical records at all regional public hospitals in Hong Kong and survey of all the registered practitioners in Hong Kong. The secondary source of validation was made impractical, if not impossible, because of the recent implementation of the Personal Data Privacy Ordinance in Hong Kong. RESULTS: A total of 255 diabetic cases were identified, 227 type 1 diabetes mellitus (218 were Chinese), 18 type 2 diabetes mellitus and 11 secondary diabetes. 246 patients were Chinese and 9 non-Chinese. The age-standardized incidence of type 1 and type 2 diabetes mellitus in southern Chinese children in Hong Kong was 1.4/100,000/yr and 0.1/100,000/yr respectively for children < 15 yr of age during the study period. The incidence rates for type 1 diabetes were 0.9, 1.5 and 1.7 per 100,000/yr for 0-4 years, 5 to 9 years and 10 to 14 years age-groups respectively. The incidence for males was 1.2/100,000/yr and for females 1.7/100,000/yr. A significant increase in the incidence was demonstrated during the study period by simple linear regression (slope 0.14/100,000/year, r2 = 0.73, p = 0.0002) CONCLUSIONS: A diabetic registry is established in Hong Kong. This study documents a very low incidence rate of childhood type 1 diabetes mellitus in southern Chinese children in Hong Kong and we have seen an increasing incidence of the disease in the past 13 years.

Goitrogenesis during pregnancy and neonatal hypothyroxinaemia in a borderline iodine sufficient area.

OBJECTIVE: Severe iodine deficiency disorders (IDDs) may have been eradicated in many parts of the world, but milder forms still exist and may escape detection. We evaluated the impact of pregnancy on the maternal and fetal thyroid axis in Hong Kong, a coastal city in southern China with borderline iodine intake. DESIGN: A prospective study performed in a maternity hospital. PATIENTS: Two hundred and thirty pregnant women were prospectively studied and their neonates assessed at birth. MEASUREMENTS: Urine iodine concentration, thyroid function tests and thyroid volume (TV) by ultrasound were determined in the mothers during pregnancy and up to 3 months postpartum and in the neonates. RESULTS: Increased urinary iodine concentration was seen from first trimester onwards and the proportion of women having urine iodine concentration of < 0.4 micromol/l decreased from 11.3% in the first trimester to 4.7% in the third trimester. There was progressive reduction in circulating fT4 and fT3 concentrations and free thyroxine index (FTI) with increasing gestation and the percentage of women having subnormal levels at term were 53.2%, 61.1% and 4.8%, respectively. The serum TSH concentration during pregnancy doubled towards term. In the first trimester, multiparous women had significantly larger TV than the nulliparous women (P < 0.001). By the third trimester, TV had increased by 30% (range 3-230%) so that the goitre incidence was 14.1%, 21.8%, 25.9% during the three trimesters of pregnancy, and 24.3% and 21.9% at 6 weeks and 3 months postpartum (ANOVA, P < 0.05). The change in thyroid volume during pregnancy correlated positively with the change in thyroglobulin (r = 0.225, P < 0.002) and negatively with urinary iodine concentration (r = - 0.149, P < 0.02). Fourteen women with excessive thyroidal stimulation in the second trimester (defined as those with thyroglobulin (Tg) concentrations in the highest tertile and FTI in the lowest tertile) were found to have lower urine iodine concentrations and larger TV (both P < 0.005) throughout pregnancy, and their neonates had higher cord TSH (P < 0.05), Tg (P < 0.05) and slightly larger TV (P = 0.06) as compared to the findings in 216 pregnant women without evidence of thyroid stimulation. Seven neonates (50%) born to these women had subnormal fT4 levels at birth. CONCLUSION: In a borderline iodine sufficient area, pregnancy posed an important stress resulting in higher rates of maternal goitrogenesis as well as neonatal hypothyroxinaemia and hyperthyro- trophinaemia. An adequate iodization program is necessary to eliminate iodine deficiency disorders during pregnancy.

Body mass index is different in normal Chinese and Caucasian infants.

Body mass index (BMI) is one of the anthropometric measurements for assessing nutritional status, body composition and adiposity in children. Racial differences in BMI between black and white children and adolescents have been shown in several studies. The aim of this study was to determine whether an ethnic difference in BMI exists between Chinese and Caucasian children in the first two years of life. The BMI of Chinese and Caucasian infants was compared so as to assess the usefulness of the National Center for Health Statistics (NCHS) growth reference data in the assessment of nutritional status of Chinese children. Mean weight, length and BMI were compared between six cohorts of Chinese children and five cohorts of Caucasian children together with the NCHS growth reference data. The changes in the mean BMI curves during the first two years of life in the two ethnic groups were entirely different but the different cohorts in the same ethnic groups displayed a similar pattern of change with age. The difference in change in BMI in the Chinese cohorts was related to the difference in change in their mean weight as compared to the NCHS weight-for-age reference data. In contrast, the change in mean length of the well-nourished Hong Kong Chinese children in the present study followed the mean NCHS height-for-age values. The results of this study suggest that linear growth would be better for the assessment of health and nutrition in infancy and early childhood. If BMI and weight-for-height standards were to be used then an ethnic group-specific and population based reference data set should be used.

A comparison of target height estimated and final height attained between Swedish and Hong Kong Chinese children.

Target height, the genetic potential in stature, is commonly estimated by the corrected midparental height (CMH) method. A new model for estimating target height has recently been introduced based on a large, Swedish, population-based study. The aim of this study was to compare the validity of the two methods for estimating target height in Hong Kong Chinese children. The Hong Kong Chinese were more than 10 cm shorter than the Swedes in stature. The secular increase in height over the two generations, however, was 4.2-4.8 cm for the Hong Kong Chinese, much larger than that of the Swedes (0.7-1.0 cm). The two populations are thus at different stages in the secular trend. The new model derived from Swedish population for estimating target height was shown to be applicable to Hong Kong Chinese children; the mean of residual final height values was close to zero (-0.15 cm, p = 0.74). However, the mean of residual final height was significantly above the expected value of zero (4.5 cm, p<0.0001) when the CMH method was applied to the data, which implies an underestimation bias of 4.5 cm. Consequently, if the CMH method is used to estimate target height and evaluate growth hormone treatment responses in short children, it may inflate the treatment response by 4.5 cm. In conclusion, the recently proposed model for target height estimation offers a better alternative for estimating target height in Hong Kong Chinese children and for assessing growth-promoting treatments.

Prevalence of peripheral neuropathy with insulin-dependent diabetes mellitus.

Insulin-dependent diabetes mellitus (IDDM) is rare in Chinese children. There have been no reports on the prevalence of peripheral neuropathy in Chinese children with IDDM. This study aimed to determine prevalence of subclinical peripheral neuropathy in Chinese children with IDDM. Motor and sensory nerve conduction studies of both median, ulnar, peroneal, and tibial (motor nerves) and median, ulnar, and sural (sensory nerves) were performed in 38 children with IDDM (18 males, 20 females). The age was 4-21 years (mean = 12.7 years; median = 12 years, 6 months). The duration of diabetes was less than 5 years in 15, 5-10 years in 14, and more than 10 years in nine. Neurophysiologic evidence of subclinical peripheral neuropathy was present in 26 patients (68.4%) of which motor, sensory, or motor and sensory involvement was 26 (68.4%), eight (21.1%), and 26 (68.4%), respectively. Twelve (31.6%) and 14 (36.8%) children had mild and moderate degrees of peripheral neuropathy, respectively. Among the 26 children with abnormal nerve-conduction studies, two (7.7%) had symptoms of numbness and pain in the lower limbs. Thus, two children had symptomatic neuropathy and most (n = 24) had asymptomatic peripheral neuropathy. Two children had systemic hypertension, and one (3.8%) had laboratory evidence of early renal complications. Analysis of demographic and laboratory risk factors for the development of subclinical peripheral neuropathy revealed that the age of onset, duration of diabetes, level of hemoglobin A1c, triglyceride, cholesterol, serum creatinine, and urea, microalbumin/creatinine ratio, and urinary microalbumin excretion rate were significantly related to the development of subclinical peripheral neuropathy in specific nerves.