Ehrlichia ewingii in an immunocompetent adult.

The third Ehrlichia infection described in humans in the United States is reviewed. This rare zoonosis was first published in 1999. This case report that expands the clinical paradigm is described. A 57-year-old immunocompetent adult, unlike previously published reports, did not cross react with Ehrlichia chaffeensis.

STARI, or Masters disease: Lone Star tick-vectored Lyme-like illness.

Lyme-like illness (also known as southern tick-associated rash illness [STARI] or Masters disease) is vectored by the Lone Star tick (Amblyomma americanum). Lyme-like illness lesions, which are similar to the erythema migrans rash of Lyme disease, tend to have lymphocytic dermal infiltrates. With the exception of Borrelia lonestari, the possible causative agent or agents of Lyme-like illness have not been cultured. More research is needed to fully understand this newly recognized zoonosis. Clinicians are encouraged to increase their knowledge and awareness of this Lyme disease mimic.

Serologic evaluation of patients from Missouri with erythema migrans-like skin lesions with the C6 Lyme test.

Southern tick-associated rash illness (STARI), also known as Masters disease, affects people predominantly in the Southeast and South Central United States. These patients exhibit skin lesions that resemble erythema migrans (EM), the characteristic skin lesion in early Lyme disease. The etiology of STARI remains unknown, and no serologic test is available to aid in its diagnosis. The C6 Lyme enzyme-linked immunosorbent assay was used to evaluate coded serum specimens from patients with STARI at two laboratory sites. The specimens tested at one site consisted of acute- and convalescent-phase samples that were obtained from nine STARI patients from Missouri and from one patient with documented Borrelia lonestari infection who acquired this infection in either North Carolina or Maryland. All of these samples were C6 negative. Seventy acute- or convalescent-phase specimens from 63 STARI patients from Missouri were C6 tested at the second site. All but one of these STARI specimens were also negative. In contrast, of nine acute- and nine convalescent-phase serum specimens obtained from culture-confirmed Lyme disease patients with EM from New York state, seven were C6 positive at the acute stage, and eight were positive at convalescence. The C6 test is negative in patients with STARI, providing further evidence that B. burgdorferi is not the etiologic agent of this disease.

Bacteriocidal activity of lizard and mouse serum for Borrelia lonestari, putative agent of a Lyme-like illness (AKA STARI or Masters disease) in Missouri.

OBJECTIVE: To determine responses of Borrelia lonestari and Borrelia burgdorferi to Eastern Fence lizard (Sceloporus undulatus) and Swiss-Webster mouse (Mus musculus) sera. RESULTS: Lizard sera lysed both Borrelia lonestari and Borrelia burgdorferi. Mouse sera lysed only Borrelia lonestari. CONCLUSIONS: Borrelia lonestari and Borrelia burgdorferi spirochetes did not survive exposure to lizard sera. Mice are reservoirs for Borrelia burgdorferi but may not be a Borrelia lonestari reservoir because spirochetes did not survive exposure to mouse sera.

Prospective clinical evaluation of patients from Missouri and New York with erythema migrans-like skin lesions.

BACKGROUND: The most common and most recognizable feature of Borrelia burgdorferi infection (Lyme disease) is the skin lesion erythema migrans (EM). An illness associated with an EM-like skin lesion, but which is not caused by B. burgdorferi, occurs in many southern states in the United States (southern tick-associated rash illness [STARI], also known as Masters disease). METHODS: Clinical features of 21 cases of EM-like skin lesions in 21 patients from Missouri were compared in a prospective study with those of 101 cases in 97 patients with EM-like skin lesions from New York. RESULTS: Among Missouri cases, the peak incidence of EM-like skin lesions occurred earlier in the year than it did among New York cases (P<.001). Case patients from Missouri were more likely to recall a tick bite than were case patients from New York (85.7% and 19.8%, respectively; P<.001), and the time period from tick bite to onset of the skin lesion was shorter among Missouri case patients (6.1+/-4.2 days and 10.4+/-6.1 days, respectively; P=.011). Missouri case patients were less likely to be symptomatic than were New York case patients (19.0% and 76.2%, respectively; P<.001), and Missouri case patients were less likely to have multiple skin lesions (4.8% and 26.7%, respectively; P=.042). EM-like lesions in Missouri cases were smaller in size than those in New York cases (8.3+/-2.2 cm and 16.4+/-11.5 cm, respectively; P<.001), more circular in shape (P=.004), and more likely to have central clearing (76.2% and 21.6%, respectively; P<.001). After antibiotic treatment, Missouri case patients recovered more rapidly than did New York case patients (P=.037). CONCLUSION: Cases of EM-like skin lesion in patients from Missouri and New York have distinct clinical presentations.

Microbiologic evaluation of patients from Missouri with erythema migrans.

BACKGROUND: Borrelia lonestari infects Amblyomma americanum, the tick species that is the most common cause of tick bites in southeast and south-central United States, and this spirochete has been detected in an erythema migrans (EM)-like skin rash in 1 patient. Therefore, B. lonestari is considered to be a leading candidate for the etiologic agent of EM in this region. METHODS: Skin biopsy specimens obtained from patients from the Cape Girardeau area of Missouri who had EM-like lesions were cultured in Barbour-Stoenner-Kelly medium and evaluated by polymerase chain reaction (PCR) targeting multiple genes. Serum specimens were tested by enzyme-linked immunosorbent assay for antibodies against sonicated whole-cell Borrelia burgdorferi. Results were compared with those obtained over the same period for patients from New York State who had EM. RESULTS: B. lonestari was not detected by PCR in any of 31 skin biopsy specimens collected from 30 Missouri patients. None of 19 cultures of Missouri skin samples that were suitable for evaluation were positive for B. burgdorferi, compared with 89 (63%) of 142 cultures of samples collected from New York State patients (P<.001). None of the 25 evaluable Missouri patients were seropositive for antibodies against B. burgdorferi, compared with 107 (75%) of 143 New York State patients (P<.001). CONCLUSIONS: Neither B. lonestari nor B. burgdorferi is likely to be the cause of EM-like skin lesions in patients from the Cape Girardeau area of Missouri. The etiology of this condition remains unknown.

Rocky Mountain spotted fever: a clinician's dilemma.

Rocky Mountain spotted fever is still the most lethal tick-vectored illness in the United States. We examine the dilemmas facing the clinician who is evaluating the patient with possible Rocky Mountain spotted fever, with particular attention to the following 8 pitfalls in diagnosis and treatment: (1) waiting for a petechial rash to develop before diagnosis; (2) misdiagnosing as gastroenteritis; (3) discounting a diagnosis when there is no history of a tick bite; (4) using an inappropriate geographic exclusion; (5) using an inappropriate seasonal exclusion; (6) failing to treat on clinical suspicion; (7) failing to elicit an appropriate history; and (8) failing to treat with doxycycline. Early diagnosis and proper treatment save lives.

Human monocytotropic ehrlichiosis, Missouri.

To determine the incidence, clinical and laboratory characteristics, and utility of molecular diagnosis of human monocytotropic ehrlichiosis (HME) in the primary care setting, we conducted a prospective study in an outpatient primary care clinic in Cape Girardeau, Missouri. One hundred and two patients with a history of fever for 3 days (>37.7 degrees C), tick bite or exposure, and no other infectious disease diagnosis were enrolled between March 1997 and December 1999. HME was diagnosed in 29 patients by indirect immunofluorescent antibody assay and polymerase chain reaction (PCR). Clinical and laboratory manifestations included fever (100%), headache (72%), myalgia or arthralgia (69%), chills (45%), weakness (38%), nausea (38%), leukopenia (60%), thrombocytopenia (56%), and elevated aspartate aminotransferase level (52%). Hospitalization occurred in 41% of case-patients. PCR sensitivity was 56%; specificity, 100%. HME is a prevalent, potentially severe disease in southeastern Missouri that often requires hospitalization. Because clinical presentation of HME is nonspecific, PCR is useful in the diagnosis of acute HME.

Erythema migrans.

Preview Because disseminated Lyme disease can be devastating, early recognition and treatment are important. The presence of erythema migrans offers the best opportunity for early diagnosis. Therefore, public awareness and patient education about the rash of Lyme disease are critical. Dr Masters gives practical pointers from his own experience in evaluation of erythema migrans and reviews current treatment recommendations.