Liver infarctions as the first manifestation of antiphospholipid antibody syndrome in pregnancy: a case report.

BACKGROUND: The differential diagnosis of abdominal pain in pregnant women is broad. Liver diseases as the origin of abdominal pain in pregnancy are rare, and severe forms occur in less than 0.1% of pregnancies. Some disorders, such as hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome and preeclampsia, are unique to pregnancy, while others, such as antiphospholipid antibody syndrome, may manifest in pregnancy but have consequences beyond the current pregnancy. All of them require prompt identification and treatment. CASE PRESENTATION: A 27-year-old Caucasian woman who was 15+1 weeks pregnant reported to the emergency department twice due to stabbing right-upper-quadrant abdominal pain. Initial laboratory testing revealed mild leukocytosis and slightly elevated liver enzymes. On second presentation, the patient was febrile and had an increased C-reactive protein concentration. Over the course of the next days, nonhemolytic anemia and thrombocytopenia emerged with elevated liver enzymes. Coagulation studies also revealed a prolongation of activated partial thromboplastin time. Magnetic resonance imaging showed nonspecific alterations in the right liver lobe, possibly corresponding to infection or infarction. A hepatic viral infection was ruled out. At that time, the most likely diagnosis was cholangitis with liver abscess formation, and antibiotic therapy was started. Further worsening of the anemia and thrombocytopenia, development of proteinuria, together with a miscarriage on the fourth day of hospitalization resulted in the tentative diagnosis of (triple-positive) antiphospholipid antibody syndrome, which was confirmed 12 weeks after the initial investigation. Treatment consisted of prompt anticoagulation with heparin and later on with a vitamin K antagonist as well as high-dose glucocorticoid therapy. There was no need for intravenous immunoglobulin therapy or plasma exchange, although we suspected a catastrophic form of antiphospholipid antibody syndrome due to infarctions of the liver, placenta, and possibly kidneys (proteinuria). The outcome was favorable. CONCLUSION: We report a 27-year-old pregnant woman whose abdominal pain was caused by liver infarctions as the first manifestation of catastrophic antiphospholipid antibody syndrome. The antiphospholipid antibody syndrome was possibly secondary to hitherto clinically silent systemic lupus erythematosus since the antinuclear antibodies were increased later on. Hydroxychloroquine therapy was initiated to prevent antiphospholipid antibody syndrome recurrence in a future pregnancy.

Elevated blood pressure linked to primary hyperaldosteronism and impaired vasodilation in BK channel-deficient mice.

BACKGROUND: Abnormally elevated blood pressure is the most prevalent risk factor for cardiovascular disease. The large-conductance, voltage- and Ca2+-dependent K+ (BK) channel has been proposed as an important effector in the control of vascular tone by linking membrane depolarization and local increases in cytosolic Ca2+ to hyperpolarizing K+ outward currents. However, the BK channel may also affect blood pressure by regulating salt and fluid homeostasis, particularly by adjusting the renin-angiotensin-aldosterone system. METHODS AND RESULTS: Here we report that deletion of the pore-forming BK channel alpha subunit leads to a significant blood pressure elevation resulting from hyperaldosteronism accompanied by decreased serum K+ levels as well as increased vascular tone in small arteries. In smooth muscle from small arteries, deletion of the BK channel leads to a depolarized membrane potential, a complete lack of membrane hyperpolarizing spontaneous K+ outward currents, and an attenuated cGMP vasorelaxation associated with a reduced suppression of Ca2+ transients by cGMP. The high level of BK channel expression observed in wild-type adrenal glomerulosa cells, together with unaltered serum renin activities and corticotropin levels in mutant mice, suggests that the hyperaldosteronism results from abnormal adrenal cortical function in BK(-/-) mice. CONCLUSIONS: These results identify previously unknown roles of BK channels in blood pressure regulation and raise the possibility that BK channel dysfunction may underlie specific forms of hyperaldosteronism.