Sternal Aspiration of Bone Marrow in Dogs: A Practical Approach for Canine Leishmaniasis Diagnosis and Monitoring

Bone-marrow aspirate material is commonly considered as one of the most sensitive tissues for a reliable diagnosis of leishmaniasis. The procedure herein described may permit less experienced veterinarians to be familiar with a quick and safe assessment method for leishmaniasis diagnosis in their patients. Animals are positioned in right lateral recumbency, and the area corresponding to the second, third, or fourth sternebra is identified and aseptically prepared. A 18-gauge needle connected to a 10？mL syringe is driven through the skin, up to the bone wall, and firmly pushed forward while rotating. Entry into the sternebra’s cavity is clearly perceived by the fall of resistance offered by the cortex. Some 2,500 sternal bone-marrow samplings were safely and efficiently performed on 887 dogs of different breeds and aging from 6 months to 14 years, during eight years of clinical activity for routine diagnosis of canine leishmaniasis in pets or for the efficacy evaluation of anti-Leishmania immunobiologicals in dogs naturally exposed to parasite transmission. Most of the samples (1716) were from 387 dogs enrolled for anti-Leishmania vaccine studies. The safety of the method was particularly assessed on these dogs that as per study protocol were submitted to repeated bone-marrow aspirations (2–4 per year) in follow-up examinations. 1. Introduction Canine leishmaniasis (CanL) has emerged as a major veterinary and public health problem in endemic areas but also in nonendemic ones where individual clinical cases or outbreaks of disease are reported, such as in northern Europe, the USA, and Canada [1–3]. Diagnosis of leishmaniasis in dogs should be based on an integrated approach considering signalment, history, clinical findings, and results of laboratory analyses aiming at Leishmania detection and/or at the evaluation the host’s immune responses [4]. Parasite detection can be achieved by microscopic demonstration of Leishmania amastigotes in macrophages of affected tissues. In dogs without clinical signs involving organs or tissues but yet suspected as having leishmaniasis because of exposure to infection risk or clinical recovery following drug treatment, a diagnostic sample should be obtained from tissues where parasites are more likely to be detected, such as spleen, bone marrow, lymph nodes, or buffy-coat from peripheral blood, in descending order of diagnostic sensitivity, respectively, [5, 6]. Part of the material sampled for cytology evaluation can be stored and, in case of negative microscopy, it can be sent to a reference laboratory for molecular