Aneurysms due to intimomedial mucoid degeneration.

OBJECTIVE: Review management of patients presenting with aneurysms due to intimomedial mucoid degeneration (IMMD). DESIGN: Retrospective analysis. SETTING: Metropolitan Vascular Service, Departments of Haematology and Pathology, University of Natal. MATERIALS AND METHODS: Case records reviewed over an 11 year period. Twenty-two patients were submitted for surgery. All had histological confirmation of disease. All patients were black African (Negro) descent and nineteen were female. Average age was 52 years. RESULTS: Fifteen patients had involvement of descending aorta and seven patients had extra-aortic involvement. Hypertension was noted in half of the patients. Seven patients presented acutely with rupture (4) and ischaemic lower limbs due to dissection (3). Total absence of clot within aneurysm lumen was a distinctive finding on ultrasound, CT-scan and angiography. Treatment followed standard vascular surgical principles. Three patients died following emergency aortic replacement. Three patients developed severe intraoperative bleeding problems following elective aortic aneurysm resection due to primary fibrinolysis. All had normal preoperative coagulation profiles. CONCLUSION: IMMD is a rare disease affecting the intima and media of vessel wall involving aortic and extra aortic vessels, predominantly in younger African females with hypertension. Lack of clot within aneurysm lumen should alert surgeon to predisposition toward bleeding diathesis. Meticulous suture technique is essential as aortic wall is friable. Medium to long term results are satisfactory.

Arterial thrombosis in nephrotic syndrome.

The nephrotic syndrome is characterized by profound changes in the turnover and concentration of most plasma proteins, including those involved in the coagulation pathways. Thromboembolic complications, especially venous, have been widely reported. Arterial thrombosis is a relatively rare complication and has been reported mainly in nephrotic children. In this report, an adult nephrotic patient who developed thromboses of his right middle cerebral and left femoral arteries is described. The patient died, and at postmortem no underlying arterial disease was found. Histology of the kidneys showed minimal change disease.

Ground water as a silica source for diatom production in a precipitation-dominated lake.

The short-term, seasonal input of ground water to a small, precipitation-dominated oligotrophic lake in northern Wisconsin amounts to less than 10 percent of the annual water budget of the lake but accounts for nearly all the external silica loading. Silica is a necessary nutrient for diatoms. A large spring diatom bloom occurs coincident with high silica inputs from ground water when other possible silica sources are low. The mass budgets of ground water and silica in the lake system demonstrate the importance of ground-water solute inputs to the lake.

Increased fibrinolysis and amyloidosis.

We studied three patients with amyloidosis who had a significant hemorrhagic disorder secondary to increased fibrinolysis. In two of the three patients, bleeding was one of the major initial problems; in the other patient, bleeding occurred later in the course of the disease. All three patients were men with primary or myeloma-associated amyloidosis (ie, immunoglobulin-related or AL). None of the patients had significantly impaired liver function at the time of the diagnosis of increased fibrinolysis. At admission, fibrinogen levels were 60, 170, and 90 mg/dL in the three patients. All three patients had short euglobulin clot lysis times (less than 30 minutes) and evidence of in vitro clot lysis. One patient appeared to respond to aminocaproic acid (EACA). In patients with amyloidosis and bleeding, fibrinolytic tests should be done; in patients with increased fibrinolysis, a diagnosis of amyloidosis should be considered.