isotretinoin and Gram-Negative-Bacterial-Infections

Gram-negative folliculitis may be the result of long-term antibacterial treatment in acne patients. It is caused by bacterial interference and replacement of the Gram-positive flora of the facial skin and the mucous membranes of the nose and infestation with Gram-negative bacteria. These Gram-negative bacteria include Escherischia coli, Pseudomonas aeruginosa, Serratia marescens, Klebsiella and Proteus mirabilis. The occurrence of Gram-negative folliculitis should be considered in acne patients in whom oral treatment with tetracyclines has not resulted in a significant improvement of acne lesions after 3-6 months' treatment. The occurrence of Gram-negative folliculitis in acne patients is believed to be generally underestimated, since correct sampling and bacteriology is rarely performed by clinicians. Gram-negative folliculitis in acne and rosacea patients is best treated with isotretinoin (0.5-1 mg/kg daily for 4-5 months).

Topics: Dermatologic Agents; Folliculitis; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Isotretinoin

Pyoderma faciale is an inflammatory disease that until now was believed to occur only in women. Bacterial pathogens have not been found in most cases, and those found included only gram-positive microorganisms. We present 2 cases consistent with pyoderma faciale--one of them a 17-year-old adolescent boy--in which gram-negative bacteria were found. Enterobacter cloacae was found in one patient, and Klebsiella oxytoca was found in the other. Needle aspiration is the technique of choice in looking for pathogens in this disease.

Topics: Adolescent; Anti-Infective Agents; Ciprofloxacin; Cloxacillin; Drainage; Enterobacter cloacae; Facial Dermatoses; Female; Gram-Negative Bacterial Infections; Humans; Isotretinoin; Klebsiella oxytoca; Male; Needles; Penicillins; Pyoderma; Staphylococcus aureus

Gram-negative folliculitis is an infection with gram-negative rods that most often occurs as a complication of prolonged broad-spectrum antibiotic therapy in patients suffering from acne and rosacea.. The bacteriologic and immunologic findings are reported in 46 patients, 39 men and 7 women, aged 16-79 (median, 28) years, with gram-negative folliculitis. Hypersensitivity reactions to various microbial recall antigens as well as granulocyte functions were evaluated. Quantitative measurements of serum levels of immunoglobulin M, G, A, and E, total complement activity, complement factors C3 and C4, and alpha-1-antitrypsin were performed.. The gram-negative organisms most frequently cultivated from nares, facial skin, and pustules were Klebsiella spp., Escherichia coli, Enterobacter spp., and Proteus spp. In all patients, deviations of one or more immune parameters were detected, including lowered serum concentrations of immunoglobulin M and alpha-1-antitrypsin, and elevated levels of immunoglobulin E. The humoral and cellular parameters were not influenced by isotretinoin therapy of gram-negative folliculitis.. These findings suggest that gram-negative folliculitis is not only a complication of long-lasting antibiotic treatment of acne and rosacea, but might be an entity of its own. Immunologic factors may play a critical role in the pathogenesis of gram-negative folliculitis.

Topics: Adolescent; Adult; Aged; alpha 1-Antitrypsin; Complement C3; Complement C4; Female; Folliculitis; Follow-Up Studies; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Immunoglobulins; Isotretinoin; Keratolytic Agents; Male; Middle Aged; Skin; Treatment Outcome