Szatmári Viktor, van Geijlswijk Ingeborg M
Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, The Netherlands.
Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, The Netherlands.
Vet Sci. 2022 Mar 15;9(3):137. doi: 10.3390/vetsci9030137.
A 9-month-old German shepherd dog was examined because of a chronic cough, exercise intolerance and labored breathing, as well as recurrent episodes of lethargy with anorexia. Multifocal severe bronchiectasis and neutrophilic bronchitis was found with thoracic computed tomography and cytology of bronchoalveolar lavage fluid, respectively. While oral azithromycin was administered, clinical signs were absent. However, stopping azithromycin lead repeatedly to presumed bacterial pneumonia within 1-2 months. With sub-antimicrobial dosed oral doxycycline (initially 1.5 mg/kg once daily for 3 months, then 0.7-0.5 mg/kg once daily for 6 months), the dog remained free from clinical signs. Bronchiectasis is characterized by marked irreversible bronchial dilation. Accumulation of intraluminal mucopurulent material and neutrophilic inflammation cause chronic cough and recurrent bacterial pneumonia. For therapy, life-long oral antibiotics are recommended. Chronic antibiotic administration, however, can select resistant bacterial strains. Though both azithromycin and doxycycline possess anti-inflammatory effects, doxycycline has these off-target properties at a sub-antimicrobial dose. In this report, a chronic sub-antimicrobial dose of doxycycline resulted in the resolution of chronic cough, exercise intolerance and labored breathing, and prevented recurrence of suspected bacterial pneumonia in the long-term in a dog with severe bronchiectasis. Beneficial effect of doxycycline is probably related to its anti-inflammatory effects rather than its antimicrobial properties.
一只9个月大的德国牧羊犬因慢性咳嗽、运动不耐受和呼吸困难，以及反复出现的嗜睡伴厌食症状而接受检查。胸部计算机断层扫描和支气管肺泡灌洗液体细胞学检查分别发现多灶性严重支气管扩张和嗜中性粒细胞性支气管炎。在给予口服阿奇霉素时，临床症状消失。然而，停用阿奇霉素后，在1 - 2个月内反复出现疑似细菌性肺炎。使用低于抗菌剂量的口服强力霉素（最初1.5毫克/千克，每日一次，持续3个月，然后0.7 - 0.5毫克/千克，每日一次，持续6个月），这只狗没有出现临床症状。支气管扩张的特征是明显的不可逆支气管扩张。管腔内黏液脓性物质的积聚和嗜中性粒细胞炎症导致慢性咳嗽和反复细菌性肺炎。对于治疗，建议终身口服抗生素。然而，长期使用抗生素会选择耐药菌株。虽然阿奇霉素和强力霉素都具有抗炎作用，但强力霉素在低于抗菌剂量时具有这些非靶向特性。在本报告中，长期给予低于抗菌剂量的强力霉素使一只患有严重支气管扩张的狗的慢性咳嗽、运动不耐受和呼吸困难症状得到缓解，并预防了疑似细菌性肺炎的复发。强力霉素的有益作用可能与其抗炎作用而非抗菌特性有关。
