Isolation of Rickettsia akari from eschars of patients with rickettsialpox.

Rickettsialpox is a cosmopolitan, mite-borne, spotted fever rickettsiosis caused by Rickettsia akari. The disease is characterized by a primary eschar, fever, and a papulovesicular rash. Rickettsialpox was first identified in New York City in 1946 and the preponderance of recognized cases in the United States continues to originate from this large metropolitan center. The most recently isolated U.S. strain of R. akari was obtained more than a half century ago. We describe the culture and initial characterization of five contemporaneous isolates of R. akari obtained from eschar biopsy specimens from New York City patients with rickettsialpox. This work emphasizes the importance and utility of culture-and molecular-based methods for the diagnosis of rickettsialpox and other eschar-associated illnesses.

An unusual combination: lipedema with myiasis.

Lipedema refers to the abnormal deposition of subcutaneous fat causing a striking enlargement of the lower extremities that is out of proportion to the upper body. Most clinicians are unaware of this disease and thus it is seldom diagnosed correctly. Cutaneous myiasis is the infestation of skin by fly larvae. We describe an unusual case of a woman with lipedema who developed cutaneous myiasis.

Increased detection of rickettsialpox in a New York City hospital following the anthrax outbreak of 2001: use of immunohistochemistry for the rapid confirmation of cases in an era of bioterrorism.

BACKGROUND: Rickettsialpox is a self-limited febrile illness with skin lesions that may be mistaken for signs of potentially more serious diseases, such as cutaneous anthrax or chickenpox. The cluster of cutaneous anthrax cases from bioterrorism in October 2001 likely heightened awareness of and concern for cutaneous eschars. OBJECTIVES: To apply an immunohistochemical technique on paraffin-embedded skin biopsy specimens for diagnosing rickettsialpox, and to compare the reported incidence of rickettsialpox before, during, and after the cluster of cutaneous anthrax cases. DESIGN: Case series. SETTING: Dermatology department in a large tertiary care hospital in New York City. PATIENTS: Eighteen consecutive patients with the clinical diagnosis of rickettsialpox from February 23, 2001, through October 31, 2002. MAIN OUTCOME MEASURES: Results of immunohistochemical testing of skin biopsy specimens and of serological testing. RESULTS: Immunohistochemical testing revealed spotted fever group rickettsiae in all 16 eschars and in 5 of the 9 papulovesicles tested. A 4-fold or greater increase in IgG antibody titers reactive with Rickettsia akari was observed in all 9 patients for whom acute and convalescent phase samples were available; 6 patients had single titers indicative of rickettsialpox infection (> or =1:64). Of the 18 patients, 9 (50%) presented in the 5 months following the bioterrorism attacks. CONCLUSIONS: Rickettsialpox remains endemic in New York City, and the bioterrorism attacks of October 2001 may have led to increased awareness and detection of this disease. Because rickettsialpox may be confused with more serious diseases, such as cutaneous anthrax or chickenpox, clinicians should be familiar with its clinical presentation and diagnostic features. Immunohistochemical staining of skin biopsy specimens, particularly from eschars, is a sensitive technique for confirming the clinical diagnosis.

Rickettsialpox in New York City: a persistent urban zoonosis.

Rickettsialpox, a spotted fever rickettsiosis, was first identified in New York City (NYC) in 1946. During the next five years, approximately 540 additional cases were identified in NYC. However, during the subsequent five decades, rickettsialpox received relatively little attention from clinicians and public health professionals, and reporting of the disease diminished markedly. During February 2001 through August 2002, 34 cases of rickettsialpox in NYC were confirmed at CDC from cutaneous biopsy specimens tested by using immunohistochemical (IHC) staining, PCR analysis, and isolation of Rickettsia akari in cell culture, as well as an indirect immunofluorescence assay of serum specimens. Samples were collected from patients with febrile illnesses accompanied by an eschar, a papulovesicular rash, or both. Patients originated predominantly from two boroughs (Manhattan and the Bronx). Only 8 (24%) of the cases were identified prior to the reports of bioterrorism-associated anthrax in the United States during October 2001, and lesions of several patients evaluated during and subsequent to this episode were suspected initially to be cutaneous anthrax. IHC staining of biopsy specimens of eschars and papular lesions were positive for spotted fever group rickettsiae for 32 patients. Of the eleven patients for whom paired serum samples were obtained, all demonstrated fourfold or greater increases in antibody titers reactive with R. akari. The 17-kDa protein gene sequence of R. akari was amplified from eschars of five patients. Four isolates of R. akari were obtained from cutaneous lesions. Possible factors responsible for the increase in clinical samples evaluated for rickettsialpox during this interval include renewed clinical interest in the disease, improved diagnostic methods, epizootiological influences, and factors associated with the recent specter of bioterrorism.

Generalized acanthosis nigricans in an otherwise healthy young child.

Acanthosis nigricans in children is usually a benign condition most commonly associated with obesity. Generalized acanthosis nigricans is a very rare condition, especially in childhood. We report a 6-year-old boy with a 4-year history of generalized hyperpigmentation and velvety thickening of the skin. Despite an extensive examination, no evidence for an underlying neoplastic or endocrinologic disease was found.

Amphotericin B-resistant Aspergillus flavus infection successfully treated with caspofungin, a novel antifungal agent.

Invasive aspergillosis is uncommon in immunocompetent hosts but is the second most common opportunistic fungal infection in immunocompromised patients. There has been a dramatic increase in the incidence of life-threatening aspergillosis during the past 2 decades, and the morbidity and mortality of these infections despite antifungal therapy remain unacceptably high. We describe a patient with amphotericin B-resistant Aspergillus flavus successfully treated with caspofungin, an agent belonging to a new class of antifungal drugs. Caspofungin shows great promise in the treatment of invasive aspergillosis.