Faculty of Veterinary Medicine, Animal Health Department, University of Córdoba, Córdoba, Spain.
Transbound Emerg Dis. 2022 Nov;69(6):3540-3547. doi: 10.1111/tbed.14717. Epub 2022 Oct 17.
Canine leishmaniasis is a parasitic zoonosis mainly caused by L. infantum; an obligate intracellular protozoan transmitted by haematophagous insects of the genus Phlebotomus, which affects dogs and wild canids. The clinical implications of this disease are highly variable, since infected animals may remain asymptomatic (absence of observable clinical signs) or present a wide spectrum of clinical alterations and degrees of severity, including the death of the animal. Symptoms such as lymphadenomegaly, alopecia, weight loss, keratoconjunctivitis and onychogryphosis are usually the first diagnostic reference available. The objectives of this study are to evaluate the validity (sensitivity, specificity and likelihood ratios) and diagnostic utility (pre-test probability) of the clinical signs commonly associated with canine leishmaniasis based on the prevalence in the area and to explore the combination of symptoms that best predicts the diagnosis of canine leishmaniasis. It is a matched case-control study in the canine population of southern Spain based on the comparison of the findings collected in the clinical history and the results of the LeisSCAN quantitative ELISA. A total of 39 cases and 78 controls were analysed. Approximately 80% of the infected animals showed signs compatible with the disease. The most frequent alterations were cutaneous (64.1%), systemic (51.3%) and oculo-nasal (30.7%). The most useful signs to support this diagnosis were alopecia and epistaxis (LR+ 6.69 and 6.0, respectively) (pre-test leishmaniasis probability is ≥70% for prevalence ≥28% when alopecia or epistaxis is present), followed by lameness (LR+ 5.0). The combinations of signs that showed greater validity were alopecia with hyperkeratosis of the snout and alopecia with onychogryphosis (LR+ > 10). None of the observed signs or their combinations resulted useful to rule out the diagnosis (LR- 0.55 to 1.15). The results found show notable differences in the diagnostic value of the clinical signs, individually and in combination, so we believe that medical decisions should be based on their diagnostic validity (LR+) and the estimation of the pre-test and post-test probability.
犬利什曼病是一种寄生虫性人畜共患病，主要由 L. infantum 引起；这是一种专性细胞内原生动物，通过嗜血性昆虫属（Phlebotomus）传播，影响狗和野生犬科动物。这种疾病的临床意义变化很大，因为受感染的动物可能没有任何症状（没有可观察到的临床症状）或表现出广泛的临床改变和严重程度，包括动物死亡。淋巴结肿大、脱毛、体重减轻、角膜结膜炎和爪变形等症状通常是最初的诊断参考。本研究的目的是评估基于该地区的流行情况，与犬利什曼病相关的常见临床症状的有效性（敏感性、特异性和似然比）和诊断效用（预测试概率），并探索最佳预测犬利什曼病诊断的症状组合。这是在西班牙南部犬类人群中进行的一项匹配病例对照研究，基于对临床病史和 LeisSCAN 定量 ELISA 结果收集的结果进行比较。共分析了 39 例病例和 78 例对照。大约 80%的感染动物表现出与疾病相符的迹象。最常见的改变是皮肤（64.1%）、全身（51.3%）和眼鼻（30.7%）。最有助于支持这一诊断的迹象是脱毛和鼻出血（LR+ 6.69 和 6.0）（当存在脱毛或鼻出血时，利什曼病的预测试验概率≥70%，流行率≥28%），其次是跛行（LR+ 5.0）。表现出更高有效性的症状组合是鼻周脱毛和过度角化以及脱毛和爪变形（LR+ > 10）。观察到的任何迹象或其组合都不能用于排除诊断（LR- 0.55 至 1.15）。研究结果表明，临床症状的诊断价值存在显著差异，无论是单独使用还是联合使用，因此我们认为医疗决策应基于其诊断有效性（LR+）和预测试验和后测试概率的估计。
