Received: 2 November 2020 Revised: 8 February 2021 Accepted: 19 April 2021 DOI: 10.1002/vetr.451 ORIGINAL RESEARCH Is signalment associated with clinicopathological findings in dogs with leishmaniosis? Maria Cabré1,2 Marta Planellas1,2 Laura Ordeix1,2 Laia Solano-Gallego2 1 Fundació Hospital Clínic Veterinari, Abstract Universitat Autònoma de Barcelona, Bellaterra, Spain Background: Canine leishmaniosis (CanL) is a common infectious disease. 2 Age, sex and breed might influence the type of clinical and pathological man- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat ifestations that dogs develop. The main objective of this retrospective cross- Autònoma de Barcelona, Bellaterra, Spain sectional study was to determine if an association between age, sex, breed and size and the clinical findings of CanL exists. Correspondence Material and methods: Dogs with a diagnosis of leishmaniosis were enrolled Laia Solano-Gallego, Departament de Medic- ina i Cirurgia Animals, Facultat de Veterinària, (n = 123). Clinical information, including signalment, clinical signs and lab- Universitat Autònoma de Barcelona, Bel- oratory abnormalities, was retrieved from medical records from different vet- laterra, Spain. erinary facilities from Catalonia. Email: laia.solano@uab.cat Results: Young dogs developed less frequently systemic signs (p = 0.0046), renal (p = 0.0019) and haematologic (p = 0.0275) abnormalities, while der- Funding information: The authors have not declared a specific grant for this research from matologic signs were more common in young and adult dogs compared with any funding agency in the public, commercial old ones (p = 0.0451). Young dogs showed proteinuria less often than adult or not-for-profit sectors. and old dogs (p = 0.0029). Young dogs did not present renal azotemia, while old dogs showed occasionally renal azotemia (p = 0.0478). Young dogs were mainly classified as mild-moderate LeishVet clinical stages of the disease, and very rarely as severe-very severe LeishVet clinical stages, compared with adult and old dogs (p = 0.0457). Purebred dogs significantly developed ulcerative dermatitis more frequently than crossbred dogs (p = 0.0460). Conclusion: This study describes that age is associated with differences in clinicopathological findings of CanL. INTRODUCTION When dogs are infected by L. infantum, the immune system can respond against the parasite with a cellular Canine leishmaniosis (CanL) is a vector-borne disease response that induces macrophages anti-Leishmania caused by Leishmania infantum. Dogs are the main activity which appears to be protective for the animal, reservoir host of the parasite, which can also infect or with a humoral non-protective response based on humans. This protozoan requires a phlebotomy sand the production of non-protective antibodies.4 The fly vector, which transmits the promastigote form, and type of predominant individual immune response is a mammal, where the intracellular amastigote form crucial in the presentation of the disease and deter- develops and replicates, to complete its cycle.1 minates the clinical signs and clinicopathological Canine leishmaniosis is endemic in more than 70 abnormalities in each dog. Clinical manifestations countries all over the world,2 especially where the can range from a mild papular dermatitis associated ecological and climate conditions are more appro- with a low humoral response and a predominance of priate for the vector. In Europe, the endemic regions parasite-specific cellular immunity, to a severe dis- are those beside the Mediterranean Sea, even though ease characterized by renal damage associated with the prevalence of leishmaniosis has increased in non- the glomerulonephritis caused by immunocomplex endemic countries due to the large number of dogs depositions due to a massive humoral response and travelling from Southern Europe and the presence of high parasite load.5 the vector in latitudes where it did not traditionally Clinical signs can be widely different and are usu- exist.3 In endemic areas, the prevalence of the disease ally non-specific. Therefore, leishmaniosis can be is frequently lower than 10%, while subclinical infec- included in a large number of differential diagnoses.5 tion is much higher.2 Cutaneous manifestations are among the most This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. © 2021 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association Vet Rec. 2021;e451. wileyonlinelibrary.com/journal/vetr 1 of 8 https://doi.org/10.1002/vetr.451 2 of 8 Veterinary Record frequent clinical sign found in sick dogs’ physical ations observed in patients suffering from the disease. examination and include non-pruritic desquamative Since the clinicopathological abnormalities of CanL dermatitis, ulcerative dermatitis, muco-cutaneous can be widely different, it would be useful for clini- nodular dermatitis and papular dermatitis.6–8 cians to know if there is any specific clinical abnormal- Common extra-cutaneous signs also include lym- ity according to signalment in order to prioritize CanL phadenomegaly, anorexia, weight lost or lethargy in their differential diagnosis. Therefore, the objective among others.5 Ocular disease is reported to occur in of this retrospective study was to determine if an asso- almost 25% of affected dogs, which can present signs ciation between age, sex, breed and size and the clini- such as blepharitis, keratoconjunctivitis, anterior cal and pathological presentation of CanL exists. uveitis and keratoconjunctivitis sicca (KCS).9 Vascular and neurological disorders can occasionally appear in sick animals.1,10,11 MATERIAL AND METHODS Typical laboratory findings are hyperglobuli- naemia, hypoalbuminaemia, mild to moderate non- Clinical data regenerative anaemia and mild to severe proteinuria among others extensively reviewed elsewhere.12 Even A total of 123 privately owned dogs with a diagnosis renal disease is the main cause of mortality in dogs of leishmaniosis made between 2000 and 2017 were due to leishmaniosis,1 renal azotaemia is not a com- retrospectively included in the present study. A signed mon clinicopathologic finding because it appears informed consent was obtained from tutors. Clinical when the damage is extensive enough to incapacitate information including signalment, clinical signs and renal function.2 laboratory abnormalities was retrieved from medical Different factors determinate the susceptibility of a records from different veterinary facilities from Cat- dog for this infection and development of the disease alonia: Fundació Hospital Clínic Veterinari (Bellaterra, such as age, sex, nutrition, host genetics, coinfec- Barcelona), Hospital Ars Veterinària (Barcelona) and tions or concomitant disease, immunosuppressive Hospital Mediterrani Veterinaris (Reus, Tarragona). conditions, cytokine environment, parasitic burden, The diagnosis of leishmaniosis was based on the virulence of Leishmania strain, previous infections presence of compatible clinical signs and/or clini- and method of transmission.5,13 A bimodal age dis- copathological abnormalities and the results of the tribution is seen in dogs with clinical leishmaniosis, diagnostic techniques performed: serology for the with a first peak found around 3 years old and a detection of Leishmania antibodies (ELISA or indirect second peak observed in dogs older than 8 years.14 immunofluorescence), and/or identification of Leish- This distribution can be explained by the fact that mania amastigotes in cytology and/or histology with more susceptible dogs manifest the disease at an or without immunochemistry for Leishmania, and/or early age, while other dogs are more resistant initially detection of Leishmania DNA with PCR.21 Dogs with but develop clinical leishmaniosis lately when the concomitant diseases were only included if clinical immune system declines or present a concomitant signs were controlled or were clinically not attributed morbidity.15 There is no agreement about sexual pre- to leishmaniosis. Moreover, laboratory test to rule out disposition to develop clinical leishmaniosis. Some other vector-borne diseases were performed when studies have reported that males are more affected by deemed clinically necessary by the clinician. the disease,15,16 although some others did not observe The information obtained through the clinical his- differences between sex.17 However, sex seems to be tory, physical examination and laboratory tests of each a major determinant of the clinical evolution, and dog was used to fill out a database. According to their immune response in hamsters infected with Leish- signalment and weight, dogs were grouped in the fol- mania spp., as male animals have an inherent risk lowing categories: male or female; purebred or cross- of increased disease severity.18 Some breeds seem bred; young (younger than 3-year-old), adult (from to have more tendency to be affected by the disease 3- to 8-year-old) or old (older than 8-year-old); small like boxer, cocker spaniel, German shepherd and sized (<10 kg), medium sized (10–20 kg) or large sized Doberman,16,19 while others like poodle or York- (20 kg). Clinical signs at the moment of the diagnosis shire terrier seem to be less frequent affected by were also recorded and grouped according the system leishmaniosis.15 Dogs with short hair and living out- affected: systemic clinical signs (i.e., low body condi- doors seem to present the disease more frequently.16,19 tion, apathy, anorexia or hyporexia, weakness, fever, The Ibizan hound rarely develop the disease due to lymphadenomegaly, hepatomegaly, splenomegaly a predominant cellular immune response against L. and epistaxis); dermatologic signs (i.e., desquamative infantum.20 dermatitis +/- alopecia, papular dermatitis, nodular Age, sex and breed might influence the type of dermatitis, ulcerative dermatitis and onychogrypho- clinical manifestation that dogs develop as well as sis); ophthalmologic signs (i.e., conjunctivitis, KCS, the outcome of infection. Although previous studies blepharitis, corneal edema and ocular mucosal dis- have reported that certain characteristics of the dogs charge); musculoskeletal signs (i.e., lameness, articu- signalment may be risk factors for CanL presenta- lar pain and muscular atrophy); gastrointestinal signs tion, it has not been studied whether signalment can (i.e., vomiting and diarrhea); and neurologic signs influence the type of clinical and pathological alter- (i.e., ataxia and lumbar pain). According to laboratory Veterinary Record 3 of 8 reference intervals, alterations in the complete blood TA B L E 1 Distribution of breed, sex, age and size of the dogs count (CBC), biochemical profile, urinalysis and studied serum electrophoresis were recorded as follows: renal Breed Number of dogs (%) azotaemia, proteinuria, hyperproteinaemia, hypoal- Crossbred 43 (35.0%) buminaemia, hyperglobulinaemia, hyperbetaglobu- Purebred 80 (65.0%) linaemia, hypergammaglobulinaemia, anaemia and thrombocytopenia. In addition, values of creatinine, Labrador retriever 9 (7.3%) urea, urine protein creatinine ratio (UPC), urine- Boxer 8 (6.5%) specific gravity, cholesterol, total protein, albumin, Golden retriever 7 (5.7%) beta-globulin, gamma-globulin, alanine transferase, German shepherd 6 (4.9%) alkaline phosphatase, red blood cells, hemoglobin, Dachshund 5 (4.1%) neutrophils and platelets were also recorded. The French bulldog 5 (4.1%) different laboratory abnormalities observed in the dogs studied were grouped according to the sys- American bully 3 (2.4%) tem affected. Dogs that presented anaemia or/and American Stafford Terrier 3 (2.4%) thrombocytopenia were considered to have haema- Greyhound 3 (2.4%) tological alterations, dogs that presented proteinuria West highland Terrier 3 (2.4%) or/and renal azotaemia were considered to have renal Other breeds 28 (22.8%) alterations, and dogs that presented one or multiple Sex Number of dogs (%) alterations in serum proteins were included in the group of dysproteinaemia. Male 72 (58.5%) Clinical stage of the disease according to Leishvet Female 51 (41.5%) clinical staging of CanL based on serological sta- Age (years) Number of dogs (%) tus, clinical signs and laboratory findings was also <3 38 (30.9%) determined.1 Disease severity was compared between 3–8 60 (48.8%) dogs suffering from a mild or moderate Leishvet clin- >8 25 (20.3%) ical stage (I-II) of the disease with those suffering a severe or very severe clinical stage (III-IV). Size Number of dogs (%) Small (<10 kg) 17 (15.0%) Medium (10–20 kg) 29 (25.7%) Statistical analysis Large (>20 kg) 67 (59.3%) The statistical analysis was performed using the R pro- gram version R 3.6.2 GUI 1.70 (R Development Core loskeletal, ophthalmologic, gastrointestinal and Team). neurologic signs were less commonly observed Statistical χ2 test was used to compare the presence (Table 2). Regarding laboratory abnormalities, alter- or absence of clinical signs and laboratory abnormal- ations in the protein electrophoresis were the most ities and the severity of the disease according to sex, frequent findings. The 89.1% of the dogs with pro- breed, age or size. Fisher´s exact probability test was tein electrophoresis evaluated (n = 110) presented applied when the expected values in any of the cells one or multiple alterations. Polyclonal hypergam- of a contingency table were below 5. Data analysis maglobulinaemia was the most common alteration of quantitative variables was performed using Man- noted (68.2%), closely followed by hyperproteinaemia Whitney U-test to compare laboratory results between (67.3%). CBC alterations were reported in 51.9% of two groups (sex and breed) and Kruskal-Wallis when the dogs evaluated (n = 77), and anaemia was the comparing three groups (age and size). Statistical sig- main alteration encountered (48.1%). In dogs in which nificance was considered at p < 0.05. biochemical profile and urinalysis was performed (n = 104), alterations on the renal parameters were RESULTS less frequently found (25%) (Table 3). Most dogs stud- ied were classified in the mild or moderate clinical Signalment and distribution of size stage of leishmaniosis (80.8%), while 19.2% of dogs were included in the severe or very severe stage of the Results of breed, sex, age and distribution of size of disease (Table 4). dogs studied are listed in Table 1. Clinical signs, laboratory abnormalities Clinical signs, laboratory abnormalities and clinical stage based on signalment and clinical stage and size The main type of clinical signs observed in the dogs Young dogs developed less frequently systemic signs included in the study were dermatologic signs (68.3%), (p = 0.0046, X2 = 10.76, df = 2), compared with the followed by systemic signs (60.2%), being lymphade- adult and old dogs, while dermatologic signs were nomegaly the most frequent one (43.9%). Muscu- more common in young and adult dogs (p = 0.0451, 4 of 8 Veterinary Record TA B L E 2 Distribution of the clinical signs of the dogs studied TA B L E 4 Distribution of the clinical stage of the dogs studied Clinical signs Number of dogs (%, 95% CI) Clinical stage (n = 104) Number of dogs (%, 95% CI) Dermatologic signs 84 (68.3%, 60.1%–76.5%) I-mild disease 11 (10.6%, 4.7%–16.5%) Ulcerative dermatitis 43 (35.0%, 26.5%–43.4%) II-moderate disease 73 (70.2%, 61.4%–79.0%) Papular dermatitis 29 (23.6%, 16.1%–31.1%) III-severe disease 13 (12.5%, 6.1%–18.9%) Desquamative dermatitis 22 (17.9%, 11.1%–24.7%) IV-very severe 7 (6.7%, 1.9%–11.6%) (+/- alopecia) Abbreviation: CI, confidence interval. Nodular dermatitis 13 (10.6%, 5.1%–16.0%) Onychogryphosis 2 (1.6%, 0.0%–3.9%) X2 = 6.199, df = 2) (Figure 1). Renal (p = 0.0019, Systemic signs 74 (60.2%, 51.5%–68.8%) X2 = 12.58, df = 2), and haematological (p = 0.0275, Lymphadenomegaly 54 (43.9%, 35.1%–52.7%) X2 = 7.182, df = 2) abnormalities were less frequently Apathy-anorexia 24 (19.5%, 12.5%–26.5%) found in young dogs compared with the adult and Body condition < 4/9 13 (10.6%, 5.1%–16.0%) old ones (Figure 1). Young dogs were mainly classi- Weakness 11 (8.9%, 3.9%–14.0%) fied in mild-moderate stages of the disease and very Epistaxis 5 (4.1%, 0.6%–7.6%) rarely in severe-very severe stages, compared with adult and old dogs (p = 0.0457, X2 = 6.172, df = 2) (Fig- Splenomegaly 5 (4.1%, 0.6%–7.6%) ure 1). Regarding dermatologic signs, purebred dogs Fever 3 (2.4%, 0.0%–5.2%) significantly developed ulcerative dermatitis more fre- Hepatomegaly 1 (0.8%, 0.0–2.4%) quently than crossbred dogs (p = 0.046, X2 = 3.983, Musculoskeletal signs 17 (13.8%, 7.7%–19.9%) df = 1). Concerning systemic signs, old dogs presented Lameness 14 (11.4%, 5.8%–17.0%) a lower body condition than young dogs (p = 0.0175, Muscular atrophy 2 (1.6%, 0.0%–3.9%) X2 = 8.090, df = 2). Weakness was more commonly found in small sized dogs (p = 0.0048, X2 = 10.66, Articular pain 2 (1.6%, 0.0%–3.9%) df = 2) than in medium and large-sized dogs. Accord- Ophthalmologic signs 15 (12.2%, 6.4%–18.0%) ing to laboratory abnormalities, young dogs showed Blepharitis 8 (6.5%, 2.2%–10.9%) proteinuria less often than older dogs (p = 0.0029, Keratoconjunctivitis sicca 3 (2.4%, 0.0%–5.2%) X2 = 11.67, df = 2). Hyperbetaglobulinaemia was more Conjunctivitis 3 (2.4%, 0.0%–5.2%) frequently observed in medium and large sized dogs Mucosal discharge 1 (0.8%, 0.0%–2.4%) than in small sized dogs (p = 0.0023, X2 = 12.17, df = 2). The only numerical haematological and biochemical Corneal edema 1 (0.8%, 0.0%–2.4 %) parameters that were significant were UPC regarding Gastrointestinal signs 13 (10.6%, 5.1%--16.0%) age and platelet number regarding sex. The results are Vomiting 8 (6.5%, 2.2%–10.9%) graphically displayed in Figures 2 and 3. Diarrhea 8 (6.5%, 2.2%–10.9%) Neurologic signs 1 (0.8% 0%–2.4%) Abbreviation: CI, confidence interval. DISCUSSION TA B L E 3 Distribution of the laboratory alterations of the dogs To the best knowledge of the authors, the results of studied this study seem to indicate, for the first time, that Laboratory findings Number of dogs (%, 95% CI) young dogs present less frequent clinicopathological Protein electrophoresis 98 (89.1%, 83.3%–94.9%) findings than older dogs with leishmaniosis. They alterations (n = 110) suffered less frequently systemic signs, renal and Polyclonal hypergamma- 75 (68.2%, 59.5%–76.9%) haematological alterations and were more prone globulinaemia to develop dermatologic signs. These results could Hyperproteinaemia 74 (67.3%, 58.5%–76%) suggest that some young dogs probably have a good Hypoalbuminaemia 66 (60%, 50.9%–69.2%) immune response against Leishmania infection and develop cutaneous lesions at an early age with less sys- Polyclonal hyperbeta- 39 (35.5%, 26.5%–44.4%) globulinaemia temic involvement. As reported previously, some skin manifestations, as papular dermatitis, appear to be Haematologic alterations 40 (51.9%, 40.8%–63.1%) (n = 77) associated with an effective cellular immune response and, consequently, with a favorable prognosis.8,22–24 Normocytic 37 (48.1%, 36.9%–59.2%) normochromic In addition, the observation of cutaneous lesions by anaemia the owners could accelerate the diagnosis of leish- Thrombocytopenia 17 (22.1%, 12.8%–31.4%) maniosis in these patients, when organic damage is minor because they have not had enough time to Renal alterations 26 (25.0%, 16.7%–33.3%) (n = 104) developed lesions associated with chronic inflamma- tion due to the presence of Leishmania. Instead, dogs Proteinuria 21 (20.2%, 12.5%–27.9%) with a non-protective humoral response and a high Renal azotaemia 10 (9.6%, 4.0%–15.3%) parasite load may develop a progressive and insidi- Abbreviation: CI, confidence interval. ous systemic-organic dissemination of the infection Veterinary Record 5 of 8 FIGURE 1 Significant results of the frequency of clinical signs, laboratory findings and clinical stage based on age F I G U R E 2 Urine protein creatinine ratio value according to age. Median value is indicated with a cross (x). Urinary protein creatinine ratio’s mean in young dogs was 0.24 (95% CI = 0.08-0.42), while in adult and old dogs was 2.27 (95% CI = 0–5.72) and 3.15 (95% CI = 0–5.72), respectively (Kruskal-Wallis’ test: p = 0.0024, X2 = 1.988, df = 2) and develop systemic clinical signs with aging. Con- which is implicated in the pathogenesis of many sequently, they might have lesions associated with age-related diseases and reduced response against immunocomplexes deposition in glomeruli, among pathogens.25–28 Unsurprisingly, old dogs studied had others,5 that cause proteinuria and renal azotaemia. a lower body condition than adult or young ones. This On the other hand, old dogs can suffer a chronic sub- finding can be explained by the fact that old animals clinical L. infantum infection since they were young, appear to have more tendency to develop systemic but when older, an impairment of immunological signs or it might be an inherent feature to their age. system or a concomitant disease might cause clinical As seen in previous studies, the majority of the dogs disease development.1 In fact, aging is negatively of the study were between 3 and 8 years old at the associated with all systems of the body, including moment of the diagnosis of CanL.16,31 the immunological system, leading to an increased In the present study, other clinical findings were susceptibility to different infectious diseases in older associated with signalment. Regarding breed, pure- patients.25–30 Both adaptative and innate immune bred dogs suffered more frequently ulcerative der- response are affected, giving as a result an impairment matitis than crossbred dogs. Ulcerative lesions due to of the skin immunological function with reduced CanL can have a variable clinical presentation because activity of T-cells and macrophages.27,28,30 Moreover, can be result of different pathological mechanisms. aging is also associated with low-grade inflammatory The most frequent type of ulcerative dermatitis seen stage and an increased cellular oxidative damage, in dogs with leishmaniosis is the ulcerative dermatitis 6 of 8 Veterinary Record F I G U R E 3 Platelets number according to age. Median value is indicated with a cross (x). Platelets’ mean was 271.61 × 103 /μl (95% CI = 64.01–479.21) in males and 320.52 × 103 /μl (95% CI = 163.33–477.71) in females (Mann-Whitney test: n1 = 31, n2 = 27, p = 0.0132) over the bony prominences, which is typically found always performed in each case and was only carried in large-sized dogs.7 Among all purebred studied, out at clinician discretion based on problem list and Labrador, boxer and German shepherd dogs were the differential diagnosis. Therefore, co-infections, that most represented, being similar to other studies.15,19 could also cause thrombocytopenia, were not ruled Therefore, the high percentage of ulcerative dermati- out in the majority of cases. Moreover, co-infections tis in purebred dogs can be explained by the fact might lead dogs towards disease progression and that the most represented breeds in the study are clinical presentation.39–41 Therefore, it would be inter- large-sized breeds that may be more predisposed to esting to perform tests for the diagnosis of other con- present ulcerative dermatitis over the bony promi- comitant vector-borne disease in patients with CanL. nences. Further studies are needed to determine a Concerning size, we also found significant results possible relationship between purebred dogs and that so far do not seem to be of clinical relevance. Even ulcerative dermatitis. No other significant association so, large breed dogs were more frequently affected by between clinicopathological presentation of CanL and CanL as previously reported.15,19 breed was found, probably due to the low number of This study also adds clinicopathological descrip- purebred dogs enrolled that prevented to compare tive information of CanL. Clinical signs and labora- different breeds. However, several papers in veteri- tory alterations were similar to the ones described in nary literature describe breed-associated immune previous studies. Although, in those previous studies disturbances29,32–34 or inherited defects35 that pre- patients did not present neurological disorders, and dispose purebred dogs to develop diseases in one or the prevalence of renal abnormalities was higher than more organs that can be also affected by L. infantum in the present study.16,42 It is likely that nowadays there infection. Besides, in the present study, purebred dogs is an increase in clinical awareness of this disease and were more commonly affected by leishmaniosis than that CanL is frequently included as differential diag- crossbred in accordance to other studies.15,19 nosis in endemic areas in Spain. Therefore, clinicians According to sex, males were more represented might do earlier diagnosis than 20 years ago, and clin- than females, as previously reported,15,16 and throm- ical signs and laboratory abnormalities at the moment bocytopenia was more frequently found in males of diagnosis might be less severe. In addition, there is than females. Thrombocytopenia is not a common limited information regarding the clinical staging that laboratory sign of CanL according to our study and dogs have in endemic areas of CanL. In the present others,16,17 and the cause of this finding is uncertain. study, most dogs included were classified in a moder- Male dogs might be more predisposed to disease ate clinical stage of the disease as recently described.43 due to intracellular pathogens such as Leishmania, The main limitations of this study included low Babesia, Ehrlichia and other rickettsial microor- number of dogs enrolled and the retrospective nature ganisms as it seems to occur in humans and mice of the study, which hinders to have homogeneous models.18,36 The pathophysiology of thrombocy- clinical data. Moreover, the combined effect of the topenia due to CanL has not been as well described different variables evaluated in the study had not and investigated as other vector-borne disease like been properly investigated. Considering that age babesiosis or ehrlichiosis.37,38 Unfortunately, diagnos- distribution can change according to breed and tic test for the detection of other pathogens were not size, it had been preferable to establish different age Veterinary Record 7 of 8 categories based on breeds and sizes. Some of the treatment and prevention of canine leishmaniosis. Vet Para- clinicopathological abnormalities found at the time sitol. 2009;165(1–2):1–18. 6. Saridomichelakis MN, Koutinas AF. Cutaneous involvement in of the diagnosis could be caused by coinfections. canine leishmaniosis due to Leishmania infantum (syn. L. cha- Ophthalmologic and neurologic signs might be under gasi). Vet Dermatol. 2014;25(2):61–72. diagnosed because a specialist did not commonly 7. Ordeix L. The spectrum of cutaneous manifestations in canine perform a complete ophthalmologic and/or neu- leishmaniosis: insights into diagnosis and immune responses. rologic examination to dogs included in the study. Bellaterra: Universitat Autònoma de Barcelona; 2018. 8. Lombardo G, Pennisi MG, Lupo T, Chicharro C, Solano-Gallego Furthermore, cutaneous lesions might not be always L. Papular dermatitis due to Leishmania infantum infection in properly defined due to the fact that not all dogs were seventeen dogs: Diagnostic features, extent of the infection and evaluated by a specialist dermatologist. Moreover, it treatment outcome. Parasites Vectors. 2014;7(1):1–11. would be interesting to include treatment protocols 9. Peña MT, Naranjo C, Klauss G, Fondevila D, Leiva M, Roura X, and outcome of dogs in the future. Finally, we believe et al. Histopathological features of ocular leishmaniosis in the dog. J Comp Pathol. 2008;138(1):32–9. that further studies with a larger number of dogs will 10. Silvestrini P, Piviani M, Alberola J, Rodríguez-Cortés A, Planel- be of benefit for a more robust study and to better las M, Roura X, et al. Serum cardiac troponin I concentrations in define the relationship between age, breed, sex and dogs with leishmaniasis: correlation with age and clinicopatho- size and the clinicopathological presentation of CanL. logic abnormalities. Vet Clin Pathol. 2012;41(4):568–74. 11. Giannuzzi AP, Ricciardi M, De Simone A, Gernone F. Neuro- logical manifestations in dogs naturally infected by Leishmania infantum: descriptions of 10 cases and a review of the literature. CONCLUSIONS J Small Anim Pract. 2017;58(3):125–38. 12. Paltrinieri S, Gradoni L, Roura X, Zatelli A, Zini E. Laboratory Clinicopathological findings described in the present tests for diagnosing and monitoring canine leishmaniasis. Vet study are similar to previous studies, and leishman- Clin Pathol. 2016;45(4):552–78. 13. Rombolà P, Barlozzari G, Carvelli A, Scarpulla M, Iacoponi F, iosis is more prevalent in males, pure breeds, dogs Macrì G. Seroprevalence and risk factors associated with expo- from 3 to 8 years old and large size dogs. Moderate sure to Leishmania infantum in dogs, in an endemic Mediter- clinical stage is commonly found in CanL. This study ranean region. PLoS One. 2021;16(1):e0244923. describes for the first time that age appears to be asso- 14. Alvar J, Cañavate C, Molina R, Moreno J, Nieto J. Canine leish- ciated with differences in clinicopathological findings maniasis. Adv Parasitol. 2004;57:1–64. 15. Miranda S, Roura X, Picado A, Ferrer L, Ramis A. Characteriza- of CanL. Young dogs present less severe disease and tion of sex, age, and breed for a population of canine leishman- are less prone to present systemic alterations than iosis diseased dogs. Res Vet Sci. 2008;85(1):35–8. adult-old dogs, while dermatologic signs are more fre- 16. Ciaramella P, Oliva G, De Luna R, Gradoni L, Ambrosio R, quently found in young and adult dogs. Cortese L, et al. 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