Prolonged disturbances of in vitro cytokine production in patients with severe acute respiratory syndrome (SARS) treated with ribavirin and steroids

Severe acute respiratory syndrome (SARS) is a new disease which has spread rapidly and widely. We wished to know whether evaluation of in vitro cytokine production could contribute to improved understanding of disease pathogenesis and to better patient management. Numbers of unstimulated and mitogen-stimulated cytokine-secreting peripheral blood mononuclear cells were measured repeatedly during and after hospitalization in 13 patients with SARS using enzyme-linked immunospot technology. Numbers of interferon-gamma, interleukin (IL)-2, IL-4, IL-10 and IL-12 secreting cells induced by T cell activators were below normal in many or most patients before and during treatment with corticosteroids and ribavirin but returned essentially to normal after completion of treatment. Staphylococcus aureus Cowan 1 (SAC)-stimulated IL-10 secreting cells were increased in early SARS but fell during treatment. SAC-induced IL-12 secreting cells were deficient before, during and long after treatment. Numbers of cells induced to produce IL-6 and tumour necrosis factor-alpha by T cell or monocyte activators were higher than normal in many early SARS patients and were still increased in some during and after treatment. We conclude that prolonged dysregulated cytokine production occurs in SARS and that future studies should be directed at improving anti-inflammatory and antiviral therapies in order to limit cytokine impairment.

Clinical phenotype of haemoglobin Q-H disease

Seven patients of Chinese origin who had haemoglobin (Hb) Q-H disease were studied. They were found to have a similar clinical phenotype to that of patients with deletional Hb H disease, who have a near identical genotypic configuration. The complete absence of Hb A in Hb Q-H disease and the similar clinical phenotype to deletional Hb H disease lends support to the observation that Hb Q-Thailand shares similar functional properties with Hb A.

Prevalence and specificity of clinically significant red cell alloantibodies in Chinese women during pregnancy--a review of cases from 1997 to 2001

Guidelines for the prevention and management of red cell alloantibodies during pregnancy, related to anti-D in particular, are well established in Caucasian populations. However, because of the racial difference of the blood group distribution, applicability to Chinese is unknown as a result of insufficient data on the prevalence and their outcome. In a retrospective review of 28,303 (21,327 Chinese) antenatal attendances from 1997 to 2001, 213 (0.79%) women were found to have a total of 230 irregular antibodies. About 137 (0.64%) were ethnic Chinese, and a total of 160 irregular antibodies were identified in their blood samples. About 58 of these Chinese women (0.27%) were found to have 66 clinically significant antibodies. There was only one case of anti-D detected in an Rh(D)-negative subject. Our study shows the overall prevalence of clinically significant antibodies in Chinese women, which was not different from that of the Western population. However, the specificities of the antibodies differ with the commonest antibodies encountered; these being anti-Mi (57.6%), anti-E (19.7%), anti-S (10.6%) and anti-c (7.6%). Neonatal jaundice was observed in 37 babies and 10 of them required phototherapy. The findings support the previous recommendation that routine antenatal antibody screening for Chinese women may not be worthwhile except in Rh(D)-negative subjects or those with an antecedent history of haemolytic disease of the newborn (HDN). The relative high incidence of anti-Mi in the present study and the local population, in general, may warrant a large-scale prospective study of pregnancy outcome in these subjects, especially in the light of the previous case reports of HDN because of anti-Mi.

Symptomatic venous thromboembolism in Hong Kong Chinese children

OBJECTIVE

To determine the incidence of venous thromboembolic disease in children of Chinese origin, and associated predisposing factors. DESIGN. Retrospective case series.

SETTING

A general, public hospital serving a population of approximately 181,000 children in Hong Kong.

PATIENTS AND METHODS

Hong Kong Chinese children under the age of 15 years who were diagnosed with a symptomatic venous thromboembolic event between 1995 and 2000 were included. Data on clinical features, predisposing factors, treatment, and outcome were obtained from review of hospital medical records.

RESULTS

Eight children (five girls and three boys) of mean age 11.5 years (range, 0-14.7 years) were included in the study. They presented with deep vein thrombosis (n=4, with pulmonary embolism in one), superior vena cava thrombosis (n=1), and cerebral venous sinus thrombosis (n=3). Predisposing factors included hereditary protein C deficiency (n=3), protein S deficiency (n=2), anticardiolipin antibodies (n=1), malignancy (n=3), recent neurosurgery (n=2), infection (n=1), with multiple predisposing factors seen in three patients. Anticoagulant therapy was prescribed in five patients, and long-term warfarin therapy was required in two cases. Venous thromboembolic disease resolved in all children, but one patient had a recurrence after cessation of warfarin therapy, and one patient had post-thrombotic syndrome.

CONCLUSION

The rate of venous thromboembolic disease in Hong Kong Chinese children was comparable to that seen in Caucasian children, with an annual incidence of 0.74 per 100,000 children. Predisposing factors, including hereditary prothrombotic conditions, were common.