Daniel M. Becker

Case Report: Venous Thromboembolism in AIDS

Recently, the authors managed three patients with AIDS and venous thromboembolism. All three were active, ambulatory, and without known risk factors for pulmonary embolism or deep venous thrombosis. One patient had a low titer for IgG anticardiolipin antibody (1:13). Two had low normal values for free protein S, and the third patient had a very low value (5%). Clinicians caring for AIDS patients should be alert to the possibility that venous thromboembolism may complicate HIV infection.

Recognition and evaluation of red blood cell macrocytosis in the primary care setting

Objective: To investigate primary care physicians’ recognition and evaluation of red blood cell (RBC) macrocytosis in adults. Design: Retrospective chart review. Utilizing a computerized laboratory result system, all complete blood counts (CBCs) with RBC indices performed between May 1986 and May 1987 were retrieved. Patients having mean corpuscular volumes (MCVs) more than three standard deviations from the mean (>98.5 fL) were selected for evaluation. Setting: The primary care clinics of a public university hospital. Patients: 138 (3.7%) of 3,805 adult outpatients had MCVs >98.5 fL, and of these, 128 (93.4%) had medical charts available for review. Results: 55 patients with elevated MCVs were not evaluated for this finding, and their mean MCV (100.6 fL) was significantly lower than that of the 73 patients who were evaluated (102.5 fL; p=0.003). The investigation of macrocytosis included vitamin B12 and folate levels consistently, and the reticulocyte count and peripheral smear were examined infrequently. Five patients had vitamin B12 deficiency, and two had hypothyroidism. Macrocytosis was ascribed to alcohol abuse in 47 patients, six of whom had no laboratory evaluation. Nine alcobolic patients with macrocytosis had other causes for this finding. Among the 55 patients whose macrocytosis was not evaluated, 12 were anemic and one had a peripheral neuropathy. Conclusions: Clinically significant and treatable disease was often associated with macrocytosis in our study. Macrocytosis was common, and its recognition and evaluation were variable in this primary care outpatient setting.Objective: To investigate primary care physicians’ recognition and evaluation of red blood cell (RBC) macrocytosis in adults.Design: Retrospective chart review. Utilizing a computerized laboratory result system, all complete blood counts (CBCs) with RBC indices performed between May 1986 and May 1987 were retrieved. Patients having mean corpuscular volumes (MCVs) more than three standard deviations from the mean (>98.5 fL) were selected for evaluation.Setting: The primary care clinics of a public university hospital.Patients: 138 (3.7%) of 3,805 adult outpatients had MCVs >98.5 fL, and of these, 128 (93.4%) had medical charts available for review.Results: 55 patients with elevated MCVs were not evaluated for this finding, and their mean MCV (100.6 fL) was significantly lower than that of the 73 patients who were evaluated (102.5 fL; p=0.003). The investigation of macrocytosis included vitamin B12 and folate levels consistently, and the reticulocyte count and peripheral smear were examined infrequently. Five patients had vitamin B12 deficiency, and two had hypothyroidism. Macrocytosis was ascribed to alcohol abuse in 47 patients, six of whom had no laboratory evaluation. Nine alcobolic patients with macrocytosis had other causes for this finding. Among the 55 patients whose macrocytosis was not evaluated, 12 were anemic and one had a peripheral neuropathy.Conclusions: Clinically significant and treatable disease was often associated with macrocytosis in our study. Macrocytosis was common, and its recognition and evaluation were variable in this primary care outpatient setting.

Venous thromboembolism: Epidemiology, diagnosis, prevention

It is difficult to es t imate the prevalence of venous thromboembol ism for the entire population. Most people who have pulmonary embolism or deep venous thrombosis a re asymptomatic . Pulmonary emboli discovered at au topsy are rarely suspec ted before death. 1 Frequencies of pulmonary emboli discovered post mortem range from 6 to 64%, depending on the hospi ta l and the pathologist . 2 In acute care general hospi tals pulmonary embol ism is found to be the sole or major contributing cause of death in 9-21% of autopsies , a l though there is recent evidence that this figure is decreasing. 3 Estimates of total annual dea ths from pulmonary embol ism in the United States range from 50,000 to 200,000. 4 The overall incidence of pulmonary embol ism has been es t imated to be 630,000. 4 Since pulmonary embol ism is usual ly a complication of deep venous thrombosis, the incidence of the latter condition would exceed that of pulmonary embolism. Aside from the morbidity and mortality of acute d i s e a s e , there a re impor tan t longte rm consequences of venous thromboembolism. Although pulmonary hyper tension as a consequence of recurrent pulmonary embol ism is rare, persistent circulatory abnormal i t ies (decreased pulmonary capillary volume and dec reased diffusion capacity) are readily demonst rab le following a single ep isode of pulmonary embolism.S Following thrombotic occlusion of the deep venous system in the thigh, the majority of pat ients t reated in the s tandard manner (i.e., hepar in as opposed to thrombolytic agents) develop venographic and clinical s igns of venous

A patient-based system for describing ambulatory medicine practices using diagnosis clusters

Objective:To develop a patient-based classification system to describe the clinical content of ambulatory medicine practices.Design:A system of 100 diagnosis clusters was developed based on retrospective review of computerized problem lists of patients from a university practice, and then applied to the problem lists of patients in a community practice. Chart review of a 5% random sample (n=184) of university practice patients who had problem lists was carried out to assess the accuracy of the computerized problem lists.Setting:A university ambulatory medicine practice and a community ambulatory medicine practice.Patients/participants:For the same one-year period, all 4,490 patients seen in the university practice and all 1,294 patients seen two or more times in the community practice.Interventions:None.Measurements and main results:Of the 27,634 problems listed for university patients and the 5,648 problems listed for community patients, 22,629 (82%) and 4,924 (87%), respectively, were assigned to diagnosis clusters. For the university and community practices, the mean numbers of problems per patient were 6.1 (SD 5.4) and 4.4 (SD 3.7), and the mean numbers of diagnosis clusters per patient were 4.5 (SD 3.7) and 3.6 (SD 3.0), respectively. Among the ten most common diagnosis clusters in both practices were HYPERTENSION, SYMPTOM OR SIGN, OBESITY, and DIABETES. Only 18% (SD 3%) of patient problem lists in the university practice omitted one or more chronic, important medical problems (e.g., hypertension, dementia, COPD).Conclusions:This system of diagnosis clusters effectively and efficiently described the clinical content of two types of internal medicine practices, and has important applications in medical education, epidemiology, clinical and health services research, and public policy.

Anticoagulation therapy and primary care internal medicine: a nurse practitioner model for combined clinical service

The anticoagulation clinics at the University of Virginia Health Sciences Center and the University of California at Davis Medical Center are nurse-practitioner-operated, are affiliated with the general medicine clinic, and rely on portable prothrombin time (PT) monitors that use whole blood and provide timely as well as accurate results reported in PT seconds or as the international normalized ratio (INR). On-site PT/INR testing at these clinics simplifies anticoagulation, mandates direct patient contact, and facilitates primary as well as comprehensive care for patients requiring multispecialty services in large tertiary care centers. Encounters are relatively brief, averaging 19 minutes; 72% of the encounter time involves anticoagulation care and 28% involves primary care. Anticoagulation results using portable PT/INR monitors are safe and accurate based on comparisons with results from clinics relying on standard instruments.

Suspected pulmonary embolism and lung scan interpretation: trial of a Bayesian reporting method.

AbstractObjective:To determine whether a Bayesian method of lung scan (LS) reporting could influence the management of patients with suspected pulmonary embolism (PE). Design:1) A descriptive study of the diagnostic process for suspected PE using the new reporting method; 2) a non-experimental evaluation of the reporting method comparing prospective patients and historical controls; and 3) a survey of physicians’ reactions to the reporting innovation. Setting:University of Virginia Hospital. Patients:Of 148 consecutive patients enrolled at the time of LS, 129 were completely evaluated; 75 patients scanned the previous year served as controls. Intervention:The LS results of patients with suspected PE were reported as posttest probabilities of PE calculated from physician-provided pretest probabilities and the likelihood ratios for PE of LS interpretations. Results:Despite the Bayesian intervention, the confirmation or exclusion of PE was often based on inconclusive evidence. PE was considered by the clinician to be ruled out in 98% of patients with posttest probabilities <25% and ruled in for 95% of patients with posttest probabilities >75%. Prospective patients and historical controls were similar in terms of tests ordered after the LS (e.g., pulmonary angiography). Patients with intermediate or indeterminate lung scan results had the highest proportion of subsequent testing. Most physicians (80%) found the reporting innovation to be helpful, either because it confirmed clinical judgement (94 cases) or because it led to additional testing (7 cases). Conclusions:Despite the probabilistic guidance provided by the study, the diagnosis of PE was often neither clearly established nor excluded. While physicians appreciated the innovation and were not confused by the terminology, their clinical decision making was not clearly enhanced.

The Addicts on Main Street

Mortality rates for middle-aged whites in the U.S. are rising due to drugs, alcohol, and depression. Unique to our country, these “deaths of despair” disproportionately occur among the under-educated, who are at particular risk for dying young. At one time, less-educated persons aspired to work in the same factory as their parents, at union wages, with benefits. Those jobs, and the sense of community and prosperity and security they allowed, are evaporating. Many former workers suffer from chronic pain, which underlies Americas ongoing opioid overdose epidemic. The pain is not only physical. It is psychic, spiritual, and economic.

Screening for Early Disease Interpretation of Diagnostic Tests

Diagnostic tests play an important role in the clinical strategies of preventive medicine. Some aspects of disease prevention are applicable to all and can be recommended unselectively. Examples include wearing seat belts and avoiding excessive use of alcohol. Other aspects of prevention require the selection of certain higher-risk groups in whom intervention would be beneficial. This selection is often done clinically, as with the use of pneumococcal and influenza vaccines in the elderly or in patients with pulmonary disease. However, many areas of preventive medicine rely on diagnostic tests in the implementation of a clinical strategy. Diagnostic tests are used in prevention in three ways.

Systemic thrombolytics for DVT were more effective than local treatment or placebo, but adverse events were more frequent

Source Citation Schweizer J, Kirch W, Koch R, et al. Short and long-term results after thrombolytic treatment of deep venous thrombosis. J Am Coll Cardiol. 2000 Oct;36:1336-43. 11028492 (All 2001 a...

Review: A prediction guide that includes clinical assessment and noninvasive tests is accurate for diagnosing deep venous thrombosis

Source Citation Anand SS, Wells PS, Hunt D, et al. Does this patient have deep vein thrombosis? JAMA. 1998 Apr 8;279: 1094-9.