Stephen E. Malawista

The Spirochetal Etiology of Lyme Disease

We recovered a newly recognized spirochete from the blood, skin lesions (erythema chronicum migrans [ECM]), or cerebrospinal fluid of 3 of 56 patients with Lyme disease and from 21 of 110 nymphal or adult lxodes dammini ticks in Connecticut. These isolates and the original one from l. dammini appeared to have the same morphologic and immunologic features. In patients, specific IgM antibody titers usually reached a peak between the third and sixth week after the onset of disease; specific IgG antibody titers rose slowly and were generally highest months later when arthritis was present. Among 40 patients who had early disease only (ECM alone), 90 per cent had an elevated IgM titer (greater than or equal to 1:128) between the ECM phase and convalescence. Among 95 patients with later manifestations (involvement of the nervous system, heart, or joints), 94 per cent had elevated titers of IgG (greater than or equal to 1:128). In contrast, none of 80 control subjects had elevated IgG titers, and only three control patients with infectious mononucleosis had elevated IgM titers. We conclude that the I. dammini spirochete is the causative agent of Lyme disease.

The Early Clinical Manifestations of Lyme Disease

Lyme disease, caused by a tick-transmitted spirochete, typically begins with a unique skin lesion, erythema chronicum migrans. Of 314 patients with this skin lesion, almost half developed multiple annular secondary lesions; some patients had evanescent red blotches or circles, malar or urticarial rash, conjunctivitis, periorbital edema, or diffuse erythema. Skin manifestations were often accompanied by malaise and fatigue, headache, fever and chills, generalized achiness, and regional lymphadenopathy. In addition, patients sometimes had evidence of meningeal irritation, mild encephalopathy, migratory musculoskeletal pain, hepatitis, generalized lymphadenopathy and splenomegaly, sore throat, nonproductive cough, or testicular swelling. These signs and symptoms were typically intermittent and changing during a period of several weeks. The commonest nonspecific laboratory abnormalities were a high sedimentation rate, an elevated serum IgM level, or an increased aspartate transaminase level. Early Lyme disease can be diagnosed by its dermatologic manifestations, rapidly changing system involvement, and if necessary, by serologic testing.

Lyme Carditis: Cardiac Abnormalities of Lyme Disease

We studied 20 patients, mostly young adult men, with cardiac involvement of Lyme disease. The commonest abnormality (18 patients) was fluctuating degrees of atrioventricular block; eight of them developed complete heart block. Thirteen patients had evidence of more diffuse cardiac involvement: electrocardiographic changes compatible with acute myopericarditis (11 patients), radionuclide evidence of mild left ventricular dysfunction (five of 12 patients tested), or frank cardiomegaly (one patient). Heart involvement was usually preceded by erythema chronicum migrans and sometimes accompanied by meningoencephalitis, facial palsy, arthritis, elevated serum IgM levels, or cryoglobulins containing IgM. The duration of cardiac involvement was usually brief (3 days to 6 weeks). The clinical picture in these patients has similarities to acute rheumatic fever; but in Lyme disease, complete heart block may be commoner, myopericardial involvement tends to be milder, and valves seem not to be affected.

Infection-induced NETosis is a dynamic process involving neutrophil multitasking in vivo

Neutrophil extracellular traps (NETs) are released as neutrophils die in vitro in a process requiring hours, leaving a temporal gap that invasive microbes may exploit. Neutrophils capable of migration and phagocytosis while undergoing NETosis have not been documented. During Gram-positive skin infections, we directly visualized live polymorphonuclear cells (PMNs) in vivo rapidly releasing NETs, which prevented systemic bacterial dissemination. NETosis occurred during crawling, thereby casting large areas of NETs. NET-releasing PMNs developed diffuse decondensed nuclei, ultimately becoming devoid of DNA. Cells with abnormal nuclei showed unusual crawling behavior highlighted by erratic pseudopods and hyperpolarization consistent with the nucleus being a fulcrum for crawling. A requirement for both Toll-like receptor 2 and complement-mediated opsonization tightly regulated NET release. Additionally, live human PMNs injected into mouse skin developed decondensed nuclei and formed NETS in vivo, and intact anuclear neutrophils were abundant in Gram-positive human abscesses. Therefore early in infection NETosis involves neutrophils that do not undergo lysis and retain the ability to multitask.Neutrophil extracellular traps (NETs) are released, as neutrophils die in vitro, in a process requiring hours, leaving a temporal gap for invasive microbes to exploit. Functional neutrophils undergoing NETosis have not been documented. During Gram-positive skin infections, we directly visualized live PMN in vivo rapidly releasing NETs, which prevented bacterial dissemination. NETosis occurred during crawling thereby casting large areas of NETs. NET-releasing PMN developed diffuse decondensed nuclei ultimately becoming devoid of DNA. Cells with abnormal nuclei displayed unusual crawling behavior highlighted by erratic pseudopods and hyperpolarization consistent with the nucleus being a fulcrum for crawling. A combined requirement of Tlr2 and complement mediated opsonization tightly regulated NET release. Additionally live human PMN developed decondensed nuclei and formed NETS in vivo and intact anuclear neutrophils were abundant in Gram-positive human abscesses. Therefore early in infection, non-cell death NETosis occurs in vivo during Gram-positive infection in mice and humans.

Treatment of the Early Manifestations of Lyme Disease

During 1980 and 1981, we compared antibiotic regimens in 108 adult patients with early Lyme disease. Erythema chronicum migrans and its associated symptoms resolved faster in penicillin- or tetracycline-treated patients than in those given erythromycin (mean duration, 5.4 and 5.7 versus 9.2 days, F = 3.38, p less than 0.05). None of 39 patients given tetracycline developed major late complications (meningoencephalitis, myocarditis, or recurrent attacks of arthritis) compared with 3 of 40 penicillin-treated patients and 4 of 29 given erythromycin (chi square with 2 degrees of freedom = 5.33, p = 0.07). In 1982, all 49 adult patients were given tetracycline; again, none of them developed major complications. However, with all three antibiotic agents nearly half of the patients had minor late symptoms such as headache, musculoskeletal pain, and lethargy. These complications correlated significantly with the initial severity of illness. For patients with early Lyme disease, tetracycline appears to be the most effective drug, then penicillin, and finally erythromycin.

Vinblastine and griseofulvin reversibly disrupt the living mitotic spindle.

Using polarized light we have studied the effects of various mitotic poisons on mitotic spindles of living Pectinaria oocytes; we have studied fixed specimens with phase and electron microscopy. Vinblastine caused attrition and eventual disappearance of spindle structure as rapidly as did colcemid, and subsequent recovery from this treatment was at least as fast as that from colcemid. Griseofulvin, however, was easily the best agent for rapid, reversible, and repeated dissolution of the spindle. Agents that arrest metaphase may act on nondividing cells by interfering with the organization of other gelated structures.

Cases of Lyme disease in the United States: locations correlated with distribution of Ixodes dammini.

Lyme disease, defined by erythema chronicum migrans and sometimes followed by neurologic, cardiac, or joint involvement, is known to have affected 512 patients in the United States. The disease seems to occur in three distinct foci: along the northeastern coast, in Wisconsin, and in California and Oregon, a distribution that correlates closely with that of Ixodes dammini in the first two areas and with Ixodes pacificus in the last. The implicated tick, saved by six patients in the Northeast, was identified as nymphal I. dammini. Residence in or travel to endemic areas and history of tick bite may be important clues to diagnosis.

Neurologic Abnormalities of Lyme Disease: Successful Treatment with High-Dose Intravenous Penicillin

Twelve patients were treated with high-dose intravenous penicillin for neurologic abnormalities of Lyme disease. Headache, stiff neck, and radicular pain usually began to subside by the second day of therapy and were often gone by 7 to 10 days. Five of the 12 patients continued to have intermittent mild headache for several more weeks, but no patient relapsed after therapy was stopped. Compared to 15 previous patients treated with prednisone alone, the duration of meningitic syndrome was significantly shorter in those given penicillin (mean duration, 1 versus 29 weeks, p less than 0.000001). However, in both groups, a mean of 7 to 8 weeks was required for complete recovery of motor deficits. Despite antibiotic therapy, 3 of the 12 patients treated with penicillin continued to have frequent arthralgias, musculoskeletal pain, and fatigue. We conclude that high-dose intravenous penicillin is effective therapy for neurologic abnormalities of Lyme disease.

Chronic Lyme Arthritis: Clinical and Immunogenetic Differentiation from Rheumatoid Arthritis

Ten patients with Lyme arthritis have developed chronic involvement of one or both knees. Lyme arthritis was diagnosed by onset with erythema chronicum migrans (six patients); residence in Lyme, Connecticut (eight); seasonal onset in summer and early fall (nine); early periods of short recurrent attacks (nine); absence of rheumatoid factor (nine); and absence of symmetrical polyarthritis, morning stiffness, subcutaneous nodules, or antinuclear antibodies (in all). Five patients had synovectomies; pannus formation and underlying cartilage erosion were present in all. Seven of the 10 patients had the same B-cell alloantigen, DRw2 (frequency in normal control subjects, 22% [P less than 0.005]), but did not have an increased frequency of the alloantigens associated with rheumatoid arthritis. Chronic Lyme arthritis, the result of an apparent tick-transmitted infection, resembles rheumatoid arthritis pathologically but generally differs from it in both prearticular and immunogenetic characteristics.

Successful Parenteral Penicillin Therapy of Established Lyme Arthritis

In a double-blind placebo-controlled trial carried out from 1980 to 1982, 20 patients with established Lyme arthritis were assigned treatment with 2.4 million U of intramuscular benzathine penicillin weekly for three weeks (total, 7.2 million U) and 20 patients received saline. Seven of the 20 penicillin-treated patients (35 per cent) had complete resolution of arthritis soon after the injections and have remained well during a mean follow-up period of 33 months. In contrast, all 20 patients given placebo continued to have attacks of arthritis (P less than 0.02). In 1983, of 20 patients treated with intravenous penicillin G, 20 million U a day for 10 days, 11 (55 per cent) had complete resolution of arthritis and have remained well since. As compared with nonresponders, penicillin-responsive patients in both studies were more likely to have previously received antibiotics for erythema chronicum migrans (P less than 0.02) and less likely to have been given intraarticular corticosteroids during or at the conclusion of parenteral therapy (P less than 0.1). The Lyme spirochete was not cultured from synovium or joint fluid. We conclude that established Lyme arthritis can often be treated successfully with parenteral penicillin. However, neither of the regimens that we tested is uniformly effective, and further experience will be needed to determine the optimal course of therapy.