Arseniasis prevalence and mortality in a multiethnic, endemic township in Guizhou, China.

OBJECTIVE: Farmers in Southwest Guizhou Autonomous Prefecture, China, represent a unique case of arseniasis, which is related to indoor combustion of high arsenic-containing coal instead of to arsenic-contaminated drinking water. A significant difference in the prevalence of arseniasis was observed in two neighboring ethnic clans in one village. The question arose whether the ethnicity-dependent difference observed in this village was more widely spread throughout the whole township. An epidemiologic investigation was designed to explore arseniasis distribution and mortality among all four ethnic groups in a multiethnic township. METHODS: The cohort of arseniasis patients, diagnosed and registered in the overall field survey of 1991 as well as all the asymptomatic residents of the township, were enrolled in the present investigation. Indirect standardization was used for calculating the age-adjusted standardized incidence ratio (SIR) of arseniasis, the standardized mortality ratio (SMR) of various death causes (including some cancers), and their corresponding intervals of 95% confidence in both genders and in each local ethnic group. RESULTS: The descending rank of arseniasis SIRs among local ethnic groups was found as: Hui>Han>Bouyei>Hmong. The descending rank of SMRs of malignancies was displayed as: Han>Hui>Bouyei>Hmong in males and both genders together as well. Concerning deaths of non-malignant causes the rank was observed as: Hui>Han>Bouyei>Hmong in males. The arseniasis SIR for ethnic Hmong residents (both genders combined) was found to be significantly less profound than the overall level in the township. No death cases in diagnosed ethnic Hmong patients and no cases of death from malignant causes in asymptomatic Hmong residents were recorded. The significant increase of arseniasis prevalence was observed in all males, compared with the overall prevalence of all residents. However, a significantly lower prevalence was seen in all females. CONCLUSION: Significant ethnicity-dependent difference in arseniasis prevalence and mortality from all causes was found in a multiethnic rural township where farmers have been exposed to the indoor combustion of high arsenic coal for decades. The ethnic Hmong residents seemed to be the least susceptible to arseniasis among the four local ethnic groups.

[Clinical application of the scapular free flap extended to the upper arm].

OBJECTIVE: To apply the scapular free flap extended to the upper arm for resurfacing the face and neck, as well as the upper lip in one stage. METHODS: The scapular free flap was designed with extended portion to the posterior and interior part of the upper arm. Then the free flap was transferred to resurface the face and neck with the routine portion and to resurface the upper lip with the extended portion. RESULTS: 6 cases with extensive upper lip, facial and cervical burn scar were treated with the extended scapular free flaps. The flap size ranged from 22 cm x 11 cm to 40 cm x 9.5 cm (36.57 cm x 10.20 cm in average) for the routine portion and from 7 cm x 4 cm to 12 cm x 4 cm (10.32 cm x 3.67 cm in average) for the extended portion. All flaps survived completely. CONCLUSIONS: There are direct communicating branches ("choke vessel") between the circumflex scapular artery (CSA) and the posterior humeral circumflex artery (PHCA). When the blood supply of PHCA is cut off, the CSA can provide blood supply through the communicating branches to the upper arm skin area previously nourished by PHCA. So the blood supply of the extended portion of the scapular free flap is not only from the branches of CSA, but also from the direct communicating branches between the CSA and PHCA. The extended scapular free flap has a reliable blood supply and can be applied to construct the facial and cervical scar contraction with the extended portion to resurface the upper lip. The satisfactory result can be expected.

[Repair of the facial defects using the expanded induced prefabricated skin flap of the retroauricular and mastoid process region based on the superficial temporal vascular bundle].

OBJECTIVE: To provide an ideal method for flap prefabrication. METHODS: The superficial temporal fascial flap has been elevated based on the superficial temporal vessels during the first-stage procedure. A subcutaneous tissue pocket with appropriate site was formed in the retroauricular and mastoid process region. The fascial flap was transferred into the pocket and fixed properly. The tissue expander was placed under the fascial flap. When the expanding process has been finished, the expander was removed and the expanded induced prefabricated skin flap of the retroauricular and mastoid process region pedicled on the superficial temporal vascular bundle was elevated and transferred to repair the facial skin defect. RESULTS: There were nine cases in the group. Facial defects after resection of the melanotic nevus was repaired in 2 cases and facial defects after resection of the facial haemangioma and scar were repaired in 2 and 5 cases respectively. Pedicle length of the superficial temporal fascial flap was ranged from 5.5 cm to 7 cm (mean length 6.2 cm). The size of the fascial flaps was ranged from 4 cm x 3 cm to 7 cm x 7 cm (mean size 5.7 cm x 4.9 cm). The size of the prefabricated skin flaps was ranged from 5 cm x 5 cm to 8.0 cm x 7.5 cm (mean size 6.4 cm x 6.1 cm). The average time of the tissue expansion process is 16.1 weeks. All flaps survived postoperatively and the donor sites of the flaps were appropriated directly in 5 cases. The split-thickness skin grafting was used to recover the donor site defects in 4 cases. CONCLUSIONS: The superficial temporal fascial flap owns the following advantages: the vascular pedicle is much longer and vascular supply is plentiful, and it is convenient to transfer. Meanwhile, the skin of the retroauricular and mastoid process region is most similar to that of the face in texture, color and depth. For the patients selected strictly, the technique mentioned above is somewhat an ideal method for facial defect repair.

A follow-up study of mortality among the arseniasis patients exposed to indoor combustion of high arsenic coal in Southwest Guizhou Autonomous Prefecture, China.

OBJECTIVE: This study was directed to ascertain the mortality of a group of arseniasis patients in an endemic rural township in Southwest China, where the residents were exposed for decades to indoor combustion of high arsenic coal. METHODS: All the diagnosed arseniasis cases registered in 1991 were defined as the target population, which were assigned to three symptom subgroups by the severity of dermal lesions. The death cases were surveyed and checked. The follow-up period was 12.5 years. The standardized mortality ratio (SMR) of all death causes combined, all cancers combined, and the cancers at every site were analyzed. The age standardized mortality rates (ASMRs) were calculated in three subgroups using the procedure of standardization. RESULTS: One hundred and six death cases were recorded. Liver cirrhosis, non-melanotic skin cancer, lung and liver cancer were the four most prevalent death causes and referred to 70.8% (75/106) of the total death cases. The mortality of all death causes combined was not higher than that of the whole of China in 2001 (SMR = 0.76, 95% CI 0.63-0.93). The crude mortality rate of non-melanotic skin cancer in males reached up to 128.66/10(5). SMRs of lung cancer and larynx cancer in males (SMRs 2.84 and 27.27, 95% CIs 1.51-4.86 and 5.61-79.62, respectively) significantly exceeded the levels for all male Chinese. ASMRs of all death causes combined, all cancers combined and non-melanotic skin cancer in males of the severe dermal symptoms subgroup were significantly higher than those in medium and/or mild dermal symptom subgroups. CONCLUSIONS: A significantly increased mortality due to lung cancer and non-melanotic skin cancer was confirmed, alike the situation in other arseniasis endemic areas in the world. No significant elevation of mortality due to liver cancer and bladder cancer was observed. Male arseniasis patients diagnosed with severe skin lesions face higher risks of malignancies and of non-melanotic skin cancer in particular in the following years.