zithromax and Pancytopenia

In addition to the well-known signs of methotrexate toxicity, rare cutaneous side effects have been described. These cutaneous signs may provide a diagnostic clue into the diagnosis of toxicity as well as facilitate early and aggressive therapy. We describe the case of a 37-year-old male, with a diagnosis of psoriasis, who developed characteristic signs and symptoms of acute methotrexate toxicity after receiving an unknown amount of intravenous methotrexate. The patient experienced a distinct change in the morphology of his existing psoriatic plaques, which became ulcerated and necrotic in the week following the methotrexate injection. Shortly after the development of cutaneous erosions, the patient developed pancytopenia, which ultimately led to his death. Ulceration and necrosis of cutaneous psoriasis plaques may serve as a herald for the impending development of life-threatening pancytopenia in patients with acute methotrexate toxicity.

Topics: Acute Kidney Injury; Adult; Azithromycin; Biopsy; Fatal Outcome; Filgrastim; Granulocyte Colony-Stimulating Factor; Humans; Immunosuppressive Agents; Leucovorin; Male; Methotrexate; Mucositis; Necrosis; Pancytopenia; Plasma; Psoriasis; Recombinant Proteins; Self Medication; Skin Ulcer; Trimethoprim, Sulfamethoxazole Drug Combination

A dog being treated with immunosuppressive doses of prednisone and azathioprine for pancytopenia of unknown origin, developed, over a 2-week period, multiple erythematous nodular lesions in the skin including footpads. Skin samples revealed lesions identical to those of human bacillary angiomatosis (BA). The nodules were composed of multifocal proliferations of capillaries, each lined by protuberant endothelial cells. The capillary clusters were separated by an oedematous connective tissue, lightly infiltrated with degenerate inflammatory cells, including neutrophils and macrophages. Tissue sections stained with Warthin-Starry silver stain revealed large numbers of positively stained bacilli in the stromal tissue, most heavily concentrated around the proliferating capillaries. Lesions of vascular degeneration and inflammation were evident. Bartonella vinsonii subsp. berkhoffii genotype 1 was independently amplified and sequenced from the blood and the skin tissue. The pathognomonic nature of the histological lesions, demonstration of compatible silver-stained bacilli in the tissue, and identification of B. vinsonii subsp. berkhoffii in the blood and tissue indicates that this is most likely the aetiologic agent responsible for the lesions. Antibiotic therapy was successful in resolving the nodules. It would appear that B. vinsonii subsp berkhoffii, like Bartonella henselae and Bartonella quintana, has the rare ability to induce angioproliferative lesions, most likely in association with immunosuppression. The demonstration of lesions identical to those of human BA in this dog is further evidence that the full range of clinical manifestations of human Bartonella infection occurs also in canines.

Topics: Angiomatosis, Bacillary; Animals; Anti-Bacterial Agents; Azathioprine; Azithromycin; Clindamycin; Dogs; Female; Immunocompromised Host; Immunosuppressive Agents; Pancytopenia; Prednisone