Treatment of Waldenstrom's macroglobulinemia with very low doses of alpha interferon

Waldenström's macroglobulinemia (WM) is a differentiated B-cell malignancy which is usually less responsive to standard chemotherapy because of low-proliferating cells. Interferon alpha has been shown to possess a therapeutic action in numerous B-cell malignancies including the early stage of chronic lymphocytic leukemia, multiple myeloma, follicular lymphoma and hairy cell leukemia. Fourteen patients with progressive WM were included in a pilot study using very low dose of interferon alpha-2a (1 Million Units 3 times a week). The mean duration of treatment was 10.3 months (range 2-44). Six of 14 (42%) patients presented an increase in the hemoglobin level (> or = 0.9 g/dL) and 4/14 (28%) had a substantial decrease of the monoclonal component (> or = 20% of reduction). Only two patients presented both types of response, while the others with an increase in the hemoglobin level had a slight decrease in the monoclonal component (MC) (1 patient), a stable MC (1 patient) or a slight increase of MC (1 patient). One additional patient had a 15% decrease of the MC with a stable hemoglobin level. Response was observed within 3 months with a median duration of 6 months. Treatment was stopped for 3 patients because of flu-like symptoms (2 patients), or thrombocytopenia (1 patient). Follow up was possible in 12 patients lasting up to a maximum of 30 months after discontinuing treatment. Seven patients died, including 4 with progressive disease, two of infection and one of cardiac failure. In the view of these results, very low dose of interferon alpha may constitute a new approach for treatment of some cases of WM.

The autologous tissue cardiac valve: a new paradigm for heart valve replacement

This is a report of early clinical experience with an autologous tissue cardiac valve, which demonstrates the feasibility of making a bioprosthesis in the operating room in 10 minutes at the time of the valve replacement operation. There were 30 implant patients (18 men, 12 women), with ages ranging from 32 to 83 years. Diagnoses included calcified aortic stenosis (n = 16), pure aortic insufficiency (n = 9), and mixed aortic stenosis and insufficiency (n = 5). Associated diagnoses have included chronic renal failure treated with dialysis (n = 1), coronary artery disease requiring concomitant coronary bypass (n = 1), ascending aortic aneurysm requiring resection (n = 3), and mitral insufficiency requiring concomitant mitral valvuloplasty (n = 2). All of the valve replacements were in the aortic position. These implanted patients are being followed up carefully according to the protocol that requires examination every 6 months for the first year and every 12 months subsequently. No patient has been lost to follow-up. Twenty-seven patients are alive and well from 1 to 22 months postoperatively. There were three deaths: two perioperative deaths (one perivalvular leak and one hemorrhage) and one infective endocarditis 1.3 years after valve replacement. All surviving patients were followed up by echocardiographic examination (mean gradient, 15.5 +/- 6.8 mm Hg at 1 year). In conclusion, the feasibility of this method and concept has been demonstrated with implants in 30 patients. The validity of the technique will be judged by clinical results and experiences in children.

[Drug interactions and antibiotics]

Situations that require the use of systemic antibiotic therapy are common and drug interactions are potentially frequent. These interactions may be deleterious and lead to reduction of therapeutic index, enhancement of toxic risk or may be favourable, with optimization of pharmacokinetics or pharmacodynamics. The mechanisms of these interactions are discussed.

An enzymatic method for assaying sulbactam in human serum: comparison with high performance liquid chromatography

An enzymatic method using nitrocefin as substrate was developed to assay sulbactam in human serum. Serum containing sulbactam was incubated with purified titrated TEM-1 beta-lactamase and nitrocefin was then added to the mixture to determine the remaining beta-lactamase activity and consequently the concentration of sulbactam. Assays were carried out on five patients with pulmonary infections receiving sulbactam plus amoxycillin iv. The values for serum sulbactam concentrations determined by the enzymatic method were compared with those determined by high performance liquid chromatography (HPLC). The correlation coefficient was 0.990 for serum sulbactam concentrations below 15 mg/L.

[Intolerance to trimethoprim-sulfamethoxazole in Pneumocystis carinii pneumonia in AIDS. Search for predictive factors]

The treatment and the prevention of Pneumocystis carinii pneumonia (PCP) is based on trimethoprim-sulfamethoxazole. However, hypersensitivity reactions occur often in HIV-infected patients. In this study, clinical and biological parameters of 27 PCP-patients treated by this drug association were analyzed. We divided the drug reactions into two groups according to the severity. A drug reaction occurred in 59.2% of the patients and was note as a mild reaction in 18.5% of the cases and as a severe reaction in 40.7%. An initial high eosinophil count was noted in patients who may present future drug reaction. This difference was more significant in patients who may present severe drug reaction. No other clinical or biological factors were predictive of hypersensitivity. The immune status of HIV-disease, drug therapy, and drug mechanisms were discussed.

Antiphospholipid antibody production during Mediterranean spotted fever

Antiphospholipid antibodies (aPLA) were discovered during the course of Mediterranean spotted fever (MSF) caused by Rickettsia conorii and characterized by endothelial cell (EC) damage resulting from this organism's tropism for EC. In two MSF patients, two types of aPLA were identified: antiphosphatidylethanolamine antibodies detected by immunological methods and lupus anticoagulant detected by clotting assays. The persistence of both aPLA for several months after the acute phase and clinical recovery might correspond to a durable immunological response to membrane damage of EC caused by R. conorii. Their possible role in the pathophysiology of microthrombi formation observed during MSF remains to be elucidated in a study on a larger number of patients.

[Syndrome of hemophagocytosis associated with infections]

Infection-related hemophagocytic syndrome was originally described in viral processes by Risdall in 1979. Recent reports have suggested associations of this syndrome with bacterial, parasitic and fungal infections. It occurs generally in immunosuppressed patients. The clinical and biological manifestations are not specific. The diagnosis is based on morphologic examination of the bone marrow showing a benign proliferation of histiocytes with hemophagocytosis. Treatment is symptomatic, however when an infectious etiology is found a specific treatment must be applied. This pathology has a poor prognosis, with a fifty percent mortality rate. When evolution is favorable, relapses are exceptional. The precise pathophysiological mechanism has not yet been determined. A better understanding of the cytokines' role should permit to consider new therapeutic routes.

[Severe pulmonary hypertension complicating a long treatment with dexfenfluramine]

The authors report a case of severe pulmonary hypertension after long-term dexfenfluramine treatment in a 48 year old man with no previous medical history. Dexfenfluramine, which has previously been reported to cause pulmonary hypertension, is an amphetamine-like anorexic agent, a pharmacological group known to predispose to this type of side effect. The possibility of this complication should be born in mind before prescribing the drug. In particular, it would seem to be particularly important not to exceed the recommended length of treatment especially as potential reversibility of pulmonary hypertension on withdrawal of the drug has been reported in one case.

[Paraneoplastic edema syndromes in acute myelomonocytic leukemia: role of TNF-alpha and IL-6?]

We report the case of a 56 year-old man in remission of a Hodgkin's disease who had an acute myelomonocytic leukemia with major edemas. Chemotherapy temporarily allowed a concomitant regression of edemas, hyperleukocytosis and tumor necrosis factor and interleukin-6 levels which were initially elevated. We discuss the role of these two cytokines in endothelium permeability disorders.

[Cardiac tamponade in severe hypothyroidism. A rare cause]

Pericardial effusion frequently occurs in patients with hypothyroidism, and this fully justifies the use of echocardiography at the time of diagnosis and during the follow-up of hypothyroidism. Signs indicating that the pericardial effusion is poorly tolerated are rare, and the development of pericardial tamponade is exceptionally reported. A case of tamponade in an elderly woman with severe hypothyroidism is described here. Some physiopathological particularities are emphasized, together with the value of echocardiography for the diagnosis and that of pericardial drainage for the treatment.

[Compression of the coronary trunk by aneurysm of the antero-left Valsalva sinus associated with acute mitral insufficiency caused by rupture of the chordae following valvular prolapse. Successful triple surgical operation in a 66-year old patient]

Tearing of the chordae is a common complication of prolapse of the mitral valve; which becomes increasingly common with age. In contrast, aneurysm of the Valsalva sinus is rare in patients over 65 years of age. The antero-left sinus is an unusual location, but may be complicated by compression of the left coronary artery, which is reported in 16 cases in the literature. The case reported is unusual due to the combination in a 66-year old subject of acute mitral incompetence, due to tearing of the chordae following prolapse of the mitral valve, and an aneurysm pressing on the coronary trunk whilst remaining asymptomatic. Complete correction of the lesions was successfully achieved by surgery.