Lyme disease in northwestern coastal California.

To determine the incidence of physician-diagnosed Lyme disease in an endemic area of California, an active surveillance program was implemented in Lake, Mendocino, Sonoma, and southern Humboldt counties. More than 200 medical care providers were called monthly for their list of suspected cases of Lyme disease. Pertinent information was abstracted from the medical record of each patient. Of 153 cases of possible early Lyme disease ascertained from July 1991 to December 1992, 37% consisted of physician-diagnosed erythema migrans. Only 58% of erythema migrans rashes were at least 5 cm in diameter. An additional 43 patients had suspicious rashes not classified as erythema migrans. Of 166 patients with possible late-stage Lyme disease, 31% had specific clinical symptoms and 75% had a positive serologic test. With an incident case defined as physician-diagnosed erythema migrans of at least 5 cm in diameter, the annual incidence of Lyme disease in northwestern coastal California according to active surveillance only was 5.5 per 100,000. The rate of Lyme disease in California is substantially lower than that in the Atlantic northeastern United States. Many suspected cases of Lyme disease in this endemic area do not meet surveillance criteria, which are intentionally restrictive. Although some of the illnesses not meeting surveillance criteria may be due to infection with Borrelia burgdorferi, it appears that Lyme disease is being overdiagnosed in this area.

Glossal abscess.

A 21-year-old man presented to our emergency department with a two-day complaint of painful swelling and protrusion of the tongue, odynophagia, dysphagia, and difficulty with speech. A nonfluctuant area of tongue swelling was identified; needle aspiration of this site produced 5 mL of pus, with considerable amelioration of symptoms. Culture of the aspirate subsequently grew Hemophilus parainfluenzae, the first such reported case of this pathogen in a glossal abscess. Glossal abscess is a rare clinical entity that may result in airway compromise and disseminated infection to other systems. The presence of a glossal abscess should be considered in all cases of tongue swelling.

Management of ventricular dysrhythmias in the prehospital and emergency department setting.

Each year approximately 1,500,000 people experience acute myocardial infarction. About 40% of them die, half before they reach the hospital. Ventricular fibrillation (VF) is a major cause of cardiac arrest, and delay in administering antiarrhythmic agents contributes to the incidence of out-of-hospital deaths. The 3 antiarrhythmic drugs currently used by paramedics for cardiac arrest are bretylium, lidocaine, and procainamide. The early use of bretylium tosylate is stressed in Advanced Cardiac Life Support protocols because of the agent's antifibrillatory properties, that is, its ability to increase the VF threshold and to block reentry. Evidence indicates that early, aggressive use of bretylium tosylate as a first-line agent improves the likelihood of successful resuscitation. Preliminary data are presented from an ongoing comparative study of prehospital use of bretylium tosylate and lidocaine for VF. One hundred seventeen cardiac arrests have occurred, 55 of which were associated with VF and are included in the study. Resuscitation was not attempted in 3 of the 55 patients at the request of the family and physician. Of the remaining 52 patients, 17 received bretylium tosylate plus lidocaine, 12 lidocaine alone, and 7 only bretylium tosylate. There were 16 patients who did not receive medications. According to the study protocol, the choice of antiarrhythmic agents was determined by the paramedic shift during which arrest occurred. Of the 52 patients treated, 16 (30%) survived. It is too soon to draw any conclusions.

Monoclonal antibodies to mouse major histocompatibility complex antigens.

As part of our continuing effort to produce a library of hybridoma antibodies specific for the products of the mouse major histocompatibility complex (MHC), nine antibodies reacting with antigens of the H-2d haplotype have been produced by cell fusion between immune spleen cells and the SP2/0.Ag.14 cell, of H-2d origin. Serological characterization revealed that seven antibodies reacted with H-2 antigens and two with Ia antigens. Of the anti-H-2 antibodies, four detected private specificities of H-2Kd or H-2Dd antigens and three detected public specificities of H-2d and other haplotypes. One of the anti-Ia antibodies detected a private Ia specificity corresponding to Ia.23 and the other detected a previously undescribed public specificity. Anti-H-2d hybridoma cells represent a potential "autoreactive" situation in that the antibodies produced by the cells should react with their own H-2 antigens unless expression of the corresponding H-2d antigens in these cells was altered. In order to examine whether H-2d antigens continued to be expressed on these anti-H-2d hybridoma cells, binding of 125I-labeled monoclonal anti-H-2Kd and/or H-2Dd antibodies was studied. Among the four hybridoma clones tested, three bound specifically three independent 125I-labeled anti-H-2d antibodies, including two cases in which binding of autologous antibodies was detected. The last clone did not bind any of the anti-H-2d antibodies, although it bound an anti-H-2k antibody, indicating selective loss of H-2d antigens. These observations demonstrate that neither loss nor retention of H-2d antigen expression on the cell surface is obligatory in hybridoma cells producing anti-H-2d antibodies.