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Autoimmune hemolytic anemia and adrenal insufficiency are rarely associated with the antiphospholipid antibody syndrome. A 49-year-old woman with a history of deep venous thrombosis and recurrent miscarriages was found to have active autoimmune hemolytic anemia after being admitted to the hospital for cholelithiasis. The patient was treated with corticosteroids and underwent laparoscopic cholecystectomy 1 month later. Two weeks after surgery she had acute adrenal insufficiency. Activated partial thromboplastin time was prolonged, and antiphospholipid antibodies were detected in significant titer. Her illness responded well to corticosteroid therapy. Her direct Coombs' test remained positive. It appears that the antiphospholipid antibody syndrome contributed to the development of venous thrombosis, recurrent miscarriages, autoimmune hemolytic anemia, adrenal insufficiency, and indirectly, pigment stone cholelithiasis in this patient.

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BACKGROUND: A program designed to identify and address specific evolving needs of residents throughout their first year has been implemented in our department of medicine. The average annual participation is 55 residents. The program includes a detailed and structured curriculum with topics and activities aimed at improving nonclinical skills that help residents function effectively during residency. METHODS: The program was developed based on a careful analysis of problems reported by graduating residents. It consists of 12 sessions in which the residents are presented with typical difficult situations they are likely to encounter during the year. At the end of each session they are provided with strategies to help them deal with the problems or even prevent problems in some cases. An important aspect of the program is the training and utilization of senior residents as group leaders. RESULTS: Eighty-five percent of the first-year residents have actively participated in the program since July 1989 despite its voluntary nature. Participants reported that the program greatly accelerated their adaptation and helped them function more effectively in the system. Senior residents recognized benefits for their professional development as well. CONCLUSIONS: The collective wisdom of past generations is often not effectively communicated to post-graduate year 1 residents. They are left to reinvent the wheel, not always with the best results. As a consequence, a great deal of stress that can be minimized is introduced into the training process. This program shows promise as an effective mechanism to deal with these challenges.

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Intrinsic transcription terminators of prokaryotes are distinguished by a common RNA motif: a stem-loop structure high in guanine and cytosine content, followed by multiple uridine residues. Models explaining intrinsic terminators postulate that the stem-loop sequence is necessary only to form structure. In the tR2 terminator of coliphage lambda, single-nucleotide changes reducing potential RNA stem stability eliminated tR2 activity, and a compensatory change that restored the stem structure restored terminator activity. However, multiple changes in the stem sequence that should have either maintained or increased stability reduced terminator activity. These results suggest that the ability of the stem-loop structure to signal transcription termination depends on sequence specificity and secondary structure.

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Among 123 patients with ringed sideroblasts on bone marrow aspirates, 85 had acquired ringed sideroblasts with primary myelodysplasia. The patients were placed in categories modified from the French-American-British classification based on percentages of ringed sideroblasts and myeloblasts in the initial bone marrow. Overall, 48% (41/85) of patients with myelodysplasia developed acute leukemia. Primary acquired sideroblastic anemia was the most favorable category with longer survival and 13.8% (4/29) leukemic conversions. Variables correlating with leukemic transformation included male sex, thrombocytopenia, neutropenia, and pseudo-Pelger-Huët neutrophils. Only two variables had independent predictive value by multivariate regression analysis: a high percentage of myeloblasts and a low percentage of ringed sideroblasts. Numerous ringed sideroblasts strongly predicts a more favorable course in myelodysplastic patients.

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In this cross-cultural study of Puerto Rican and Texas physicians, we have tested the hypothesis that physicians' "humanistic attributes" are culturally related. Differences (P = .05 to .01) were found between mean responses of the two groups of residents to seven of the questions on the Totalitarian-Authoritarian-Dogmatism scale. Factor analysis determined that the two principal components of disagreement were medical political and ethical issues (P = .001) but not patients and their problems. Faculty responses provided additional evidence that customs and traditions influence how professional subgroups manifest attitudes: Puerto Rican faculty rated residents highest on "humanistic traits" if they self-reported high ethical scores, and lowest if they self-reported high radical scores; Baylor faculty reflected the "age-drag" on changing values by differing (P = .05 to .001) from both groups of residents on 38% of the questions. The difficulty of rating residents with a universal standard of "humanistic traits" is supported by the culture and age-specific differences reported herein.

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The American Board of Internal Medicine (ABIM) has charged directors of residency programs with evaluating "humanistic attributes" in residents seeking certification. To investigate whether traditional measures of residents' performance assess humanistic attributes, 38 second- and third-year medical residents completed the Totalitarian-Authoritarian-Dogmatism (TAD) and Rokeach tests for attitudinal assessment. Five primary sources were used to measure performance. When the measures of performance and attitude were correlated, two negative correlations with "antipathy toward patients" were found: professional maturity (r = -.43, P less than .01) and compassion and concern for patients (r = -.35, P less than .04). The TAD Opinionnaire and the special performance evaluation detect "nonhumanistic dimensions" that routine faculty assessments do not. Since the new Likert scale distributed by ABIM does not differ materially from the rating form used at Baylor for 2 1/2 years, it is unlikely that "humanistic attributes" will be measured by the ABIM's new scale.

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Five new cases of plasma cell dyscrasia with coexistent myelofibrosis are described and six previously reported cases are reviewed. Four of the new patients and two from the literature had features of a previously unrecognized syndrome. This syndrome was characterized by significant paraprotein levels, marked marrow fibrosis, and plasmacytosis, without features of extramedullary hematopoiesis (agnogenic myeloid metaplasia) and leukoerythroblastosis. These patients were generally severely anemic and commonly leukopenic and thrombocytopenic. In contrast, one of the new patients and four in the literature showed classic features of the myeloproliferative disease, myelofibrosis with agnogenic myeloid metaplasia, along with features of typical multiple myeloma.

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Of 14 patients with hairy cell leukemia (HCL), four developed opportunistic granulomatous infections: blastomycosis, coccidioidomycosis and two Mycobacterium kansasii. The former two pathogens have not been reported with HCL, while M. kansasii infections appear to be common. While most reviews stress susceptibility to pyogenic bacteria and the predisposing role of iatrogenic factors, three of our patients were infected prior to any therapy. Thus, disease-related factors predispose to these granulomatous infections. Granulocytopenia and monocytopenia were present; the latter was not often corrected by splenectomy. There was impaired granuloma formation, with all infectious lesions appearing histologically as focal microabscesses containing few macrophages. Awareness of the frequency of opportunistic intracellular infections with early consideration of invasive diagnostic procedures to establish specific etiologic diagnosis may greatly prolong survival for many HCL patients.

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We have identified a remarkable ion-channel forming material in virulent strains of Entamoeba histolytica that may be responsible for many of the symptoms associated with amoebic dysentery. A polypeptide that we refer to as amoebapore is shed into the growth media and is also found within the amoeba in a high speed sedimentable fraction. Amoebapore has the distinctive property of spontaneously incorporating into lipid bilayers, liposomes, and cells, leading to progressive and irreversible changes in the ion conductance of the target membranes. Exposure of planar lipid bilayers to amoebapore -containing fractions under voltage clamp conditions results in an almost immediate and progressive incorporation of ion channels which continues in an irreversible manner leading to a fall in membrane impedance of up to five orders of magnitude. The ion-channel conductance is moderately cation-selective, voltage dependent, and displays a unit size of 1.6 +/- 0.2 nanoSiemens in 1 M KCl at -10 mV. In the bilayer, the amoebapore -induced conductance exhibits an in situ sensitivity to protease. Amoebapore is mainly concentrated in a fraction sedimenting at 150 000 g. It is insoluble in Triton X-100 but can be dissociated in an active state in 1% SDS. Under these conditions it has an apparent mol. wt. of 13 000 daltons.

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As calcium has increasingly been the object of study in erythrocyte physiology, we reviewed the current methodologies for determination of calcium by atomic absorption spectrometry. The published normal values for erythrocyte calcium vary from 5 to 500 mumol/liter of packed cells. A method based on Harrison and Long's determination of calcium is presented and shows normal red cell calcium concentration to be 0.0149 +/- 0.0023 mumol/ml of packed red cells. The influence of temperature and type of crucible used in ashing red cells is assessed. The method of additions is employed to corroborate our results.

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We describe a patient with a myelodysplastic syndrome characterized by pancytopenia and an excess of myeloblasts in the bone marrow. He had received massive doses of diethylstilbestrol (150 mg daily) for seven years as therapy for prostatic carcinoma. Although myelodyspoiesis has been associated with other drugs, a relationship to estrogen therapy in man has not been reported previously. However, the administration of estrogens to animals has produced pancytopenia with a relative monocytosis and vacuolization of leukocytes. Examination of bone marroa, erythroid hypoplasia, and, with prolonged therapy, aplastic anemia. Further animal studies have demonstrated that estrogens exert a suppressive effect on marrow stem cells and granuloid progenitor cells. These experimental observations suggest a possible role of estrogens in the genesis of the hematologic changes we observed.

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A method is given for the in vitro evaluation of transfusion therapy of patients with sickle cell anemia. Changes in volumetric flow rate, hemoglobin flow rate, and oxygen delivery at three values of PO2 (25, 40, and 80 mmHg) induced by transfusion of two units of AA blood in three patients are evaluated. The viscosity-shear rate data are obtained in a precision cone and plate viscometer with controlled environment. This data is then used to calculate flow rates in model tubes of varying diameters (50-500 microns). The increase in oxygenated hemoglobin flow rates at low oxygen tensions after transfusion can be striking-sometimes greater than a factor of two. A preliminary evaluation of the potential effect of auto-transfusion or androgen therapy on these flow rates is also discussed.

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Four patients with Coombs'-positive hemolytic anemia associated with carcinoma are presented and compared to 12 previously described patients. These patients commonly seek medical attention for symptoms of anemia rather than for complaints due to the tumor mass. The physician should particularly evaluate for an underlying carcinoma when a patient over the age of 60 years presents with autoimmune hemolytic anemia. Autoimmune hemolytic disease has been demonstrated in patients with a wide variety of tumors, including squamous cell carcinomas, adenocarcinomas, hypernephromas, oat cell carcinomas and a seminoma. Corticosteroid treatment is less effective in autoimmune hemolytic disease associated with carcinoma than in idiopathic autoimmune hemolysis. Tumor extirpation in patients with localized neoplastic disease may abolish the autoimmune hemolytic anemia. Control of the carcinoma through irradiation and chemotherapy together with corticosteroid therapy and/or splenectomy lessened the anemia in some patients. The positive Coombs' test may revert to negative with tumor excision or control. Subsequently, the positivity of the Coombs' reaction may provide a clue to recurrent neoplastic activity. The pathogenic mechanism underlying the association between carcinoma and autoimmune hemolytic disease is poorly understood.

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Acute renal failure may be a contributory cause of death in patients with acute leukemia. The purpose of this study was to define the causes and course of acute renal failure in group of patients with acute leukemia in order to identify preventive measures and reversible aspects of the renal insufficiency. Among 88 patients with acute leukemia whose courses were followed to the time of death, ten developed acute renal failure. Etiologic factors of the renal failure were uric acid nephropathy, sepsis with complicating hypotension and hypovolemia, and the administration of nephrotoxic antibiotics. In one patient ureteral obstruction from clots was responsible for renal failure, while in another patient disseminated aspergillosis led to renal failure. Other causes of acute renal failure in persons with acute leukemia, but not observed in this patient group, are hypercalcemia and leukemic infiltration of the kidneys.

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