Influence of estrogen replacement therapy on airway reactivity.

The effect of estrogen on smooth muscle in various organs is unpredictable. Little is known about the effect of estrogen on respiratory tract smooth muscle, particularly in humans. In the present study we used the histamine challenge test (HCT) to assess the effect of estrogen replacement therapy (ERT) on airway reactivity in postmenopausal women who did not suffer from respiratory disease. Thirty-six women who were undergoing treatment at the postmenopausal clinic completed the study. All participants were nonsmokers whose pulmonary function tests were normal. HCT was performed twice before the inception of ERT, and a third time 4-6 weeks after ERT was begun. None of the 36 women demonstrated a 20% decrease in FEV1 values (PC20) after inhaling histamine at a concentration of 8 mg/ml, either before or during ERT. The maximal decrease in FEV1 values in response to the maximum concentration of histamine was significantly lower during ERT compared to the pretreatment period. The average maximal decrease in FEV1 during ERT was 2.63 +/- 2.72% (mean +/- DS) compared to 5.21 +/- 4.47% and 6.57 +/- 5.28% on the 2 tests prior to therapy (p < 0.0002). We conclude that ERT has an inhibitory effect on the bronchial reactivity of respiratory smooth muscle. There is no cause for concern about increased airway reactivity as an adverse effect of this therapy.

Adult respiratory distress syndrome as a complication of acute pyelonephritis during pregnancy.

Two cases of ARDS as a complication of acute pyelonephritis during pregnancy are presented. The severity of the clinical condition necessitated treating both patients by mechanical ventilation with high positive-end expiratory pressure. The review of the only six other similar cases already reported (only one needing vigorous respiratory treatment) as well as the two cases presented in this report show that the pyelonephritic aetiology of ARDS in pregnancy is very rare. Nevertheless, any septic condition could be complicated by respiratory failure in pregnancy. ARDS must be suspected in those patients suffering from urinary tract infection in which signs of hypoxia appeared during the third trimester of pregnancy. Early recognition of the syndrome, closed monitoring and vigorous treatment can prevent maternal complications and/or fetal distress.