Melanonychia striata in Chinese children and adults.

BACKGROUND: There is considerable racial variation in the occurrence of melanonychia striata. The prevalence of melanonychia striata in the Chinese population is not known. The purpose of this study was to investigate the prevalence and characteristics of melanonychia striata in a Chinese population of patients. METHODS: Two thousand, four hundred and fifty-seven Chinese patients attending an Asian medical clinic were examined for the presence of melanonychia striata in a cross-sectional prevalence survey. The examinations were carried out as part of the routine medical care provided to these patients. Patients of mixed racial background were excluded. The fingernails and toenails of each patient were examined, and the presence or absence of melanonychia striata, the anatomic distribution of the lesion, and the age and sex of the patient were recorded. RESULTS: Melanonychia striata was not detected in patients aged less than 20 years. The condition was present in 0.6% of patients aged between 20 and 29 years. Thereafter, the prevalence increased gradually to 1.7% in patients aged 50 years and over. There was a significant relationship between age and the presence of melanonychia striata (chi(2) = 141, P < 0.01). There was no significant sex-related difference in the age-specific prevalence (P > 0.05). The thumbs were most frequently affected, followed by the index fingers (P < 0.001). The condition was bilateral in 40% of cases. None of the patients had involvement of more than two digits. CONCLUSION: Melanonychia striata is uncommon in Chinese individuals, especially in those aged under 20 years. The male to female ratio is approximately equal. The thumbs are most frequently affected and the condition is often bilateral.

Herpes zoster in childhood.

Herpes zoster is caused by reactivation of latent varicella-zoster virus that resides in a dorsal root ganglion. Herpes zoster can develop any time after a primary infection. Because varicella vaccine is a live attenuated virus, herpes zoster can develop in a vaccine recipient. The incidence of herpes zoster among vaccine recipients is about 14 cases per 100,000 person-years. In young children, herpes zoster has a predilection for areas supplied by the cervical and sacral dermatomes. The most common complications are secondary bacterial infection, depigmentation, and scarring. Although the diagnosis of herpes zoster is based on a distinct clinical appearance, viral DNA analysis of the lesion by polymerase chain reaction or restriction fragment length polymorphism is necessary to differentiate wild from vaccine-type viruses. Acyclovir is the treatment of choice for herpes zoster.

Internipple distance and internipple index.

OBJECTIVE: To determine the internipple distance and internipple index in Chinese children. METHODS: The internipple distance and chest circumference were measured in 3,290 healthy Chinese children (1,715 males and 1,575 females) aged birth to 18 years seen at the Asian Medical Centre. The internipple distance and chest circumference were obtained at the end of expiration whenever possible, with a standard nonstretch tape measure graduated in millimeters with the arms hanging relaxed alongside the body. Patients under two years of age were measured supine and those over two years of age standing. The internipple distance was measured between the centers of both nipples, and the chest circumference was measured across the internipple line. The internipple index was calculated according to the formula: internipple distance (cm) multiplied by 100 and divided by chest circumference (cm). RESULTS: The internipple distance and chest circumference increased with age. The internipple index was highest in the neonatal period (26.4 +/- 1.6 for males and 26.3 +/- 2 for females), and decreased steadily until the age of four years (23.8 +/- 1.2 for males and 23.8 +/- 1.4 for females), and thereafter was relatively constant through the age of 18 years in males and the age of 11 years in females. In females, the internipple index decreased gradually from the age of 11 years to 18 years. CONCLUSIONS: While internipple index is a more practical way to assess nipple placement, there are ethnic differences in the internipple index. Proper reference standards should be used in the assessment whether the nipples are closely or widely spaced.