RESUMO
Peripheral gamma-delta T-cell proliferations are encountered in reaction to certain infections and in primary malignancies. Identifying sources of benign reactions is key in avoiding unnecessary workup and surveillance of these aggressive malignancies. Borrelia infections have been implicated in a number of lymphoproliferative disorders, but rarely, if ever, in this setting. While gamma-delta T-cells are known to play a prominent role in the immune response to Borrelia infection, B-cell differentiation is encountered in the majority of Borrelia-associated proliferations. We present here a unique case of benign-appearing peripheral gamma-delta T-cell lymphoid proliferation in the setting of a tick-bite with subsequent erythema migrans-like skin findings.
Assuntos
Mordeduras e Picadas/complicações , Doença de Lyme/complicações , Transtornos Linfoproliferativos/sangue , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/metabolismo , Carrapatos , Idoso de 80 Anos ou mais , Animais , Humanos , Transtornos Linfoproliferativos/microbiologia , MasculinoRESUMO
OBJECTIVE: Test D-methionine (D-met) as an otoprotectant from kanamycin-induced ototoxicity and determine the lowest maximally protective D-met dose. DESIGN: Auditory brainstem responses (ABR) were measured at 4, 8, 14, and 20 kHz at baseline and two, four, and six weeks after kanamycin and D-met administration initiation. ABR threshold shifts assessed auditory function. Following six-week ABR testing, animals were decapitated and cochleae collected for outer hair cell (OHC) quantification. STUDY SAMPLE: Eight groups of 10 male pigmented guinea pigs were administered a subcutaneous kanamycin (250 mg/kg/dose) injection once per day and an intraperitoneal D-met injection (0 (saline), 120, 180, 240, 300, 360, 420, or 480 mg/kg/day) twice per day for 23 days. RESULTS: Significant ABR threshold shift reductions and increased OHC counts (p ≤ 0.01) were measured at multiple D-met-dosed groups starting at two-week ABR assessments. A 300 mg/kg/day optimal otoprotective D-met dose provided 34-41 dB ABR threshold shift reductions and OHC protection. Lesser, but significant, D-met otoprotection was measured at lower and higher D-met doses. CONCLUSIONS: D-met significantly reduced ABR threshold shifts and increased OHC percentages compared to kanamycin-treated controls. Results may be clinically significant particularly for multidrug-resistant tuberculosis patients who frequently suffer from kanamycin-induced hearing loss in developing countries.
