Hemato-biochemical evaluation of medically managed bitches affected with pyometra

Introduction

Pyometra is a life-threatening uterine disorder in intact female dogs that commonly affects older nulliparous bitches during the luteal phase of the estrous cycle, when circulating progesterone levels are elevated (Pretzer 2008 [20] and Santana et al., 2021 [23] ). The disease is characterised by bacterial infection and inflammation of the uterus, resulting in the accumulation of purulent exudate within the uterine lumen along with systemic illness (Fransson 2003 [5] and Hagman 2012 [9] ). In pyometra affected bitches, bacteremia, endotoxemia and systemic inflammatory responses may lead to dysfunction of vital organs such as the heart, liver, kidneys and bone marrow, thereby increasing the risk of severe systemic complications and sudden death (Chitra, 2025) [2] . Although ovariohysterectomy remains the treatment of choice, medical management is considered an alternative approach in breeding bitches where preservation of fertility is desired (Hagman, 2018) [11] . Evaluation of hemato-biochemical parameters during medical management plays an important role in assessing disease severity, extent of systemic involvement and therapeutic response in affected bitches. Therefore, the present study was undertaken to evaluate the hemato-biochemical changes associated with medical management of pyometra in bitches.

Materials and Methods

The bitches presented with a history of loss of appetite, polyuria, polydipsia, vomiting, abdominal enlargement and vaginal discharge were subjected to detailed hemato-biochemical and ultrasonographic examinations for confirmation of pyometra. The selected animals were randomly assigned into two treatment groups (I and II) comprising six bitches each. Animals in Group I were treated with aglepristone @ 10 mg/kg body weight SC on days 1, 2 and 8. Animals in Group II were treated with mifepristone @ 2.5 mg/kg body weight PO for up to 5 days along with misoprostol @ 5 mcg/kg body weight PO. Depending on the clinical condition of each case, supportive therapy consisting of intravenous fluids and antibiotics was provided. The progress of treatment was evaluated through periodic clinical examination along with hematological, biochemical and ultrasonographic assessments on days 1, 5 and 8. Hematological parameters such as hemoglobin (g/dl), total erythrocyte count (x10 6 / μl), total leucocyte count (x10 3 μl), packed cell volume (%), differential leucocyte count were estimated. Biochemical analysis included estimation of total protein (g/dl), albumin (g/dl), globulin (g/dl), alanine aminotransferase (IU/L), aspartate aminotransferase (IU/L), alkaline phosphatase (IU/L), blood urea nitrogen (mg/dl) and creatinine (mg/dl). The data obtained was statistically analyzed according to Snedecor and Cochran (1994) [26] using repeated measures ANOVA in SPSS version 23.

Results and Discussion

Hematological and biochemical parameters were evaluated on the day of presentation (Day 1), and on Day 5 and 8 of treatment (Table 1 and2). The mean Hb concentration (g/dl) remained below the normal range throughout the observation period, while PCV (%) and TEC (×10 6 /µL) values were reduced on the day of presentation in both treatment groups (Table 1). Similar findings in pyometra-affected bitches were reported by Unnikrishnan et al. (2020) [28] , Demeli et al. (2023) [3] , Paudel et al. (2023) [17] and Chitra (2025) [2] . The reduced Hb, PCV and TEC values observed in the present study might be attributed to chronic inflammatory anemia, toxic suppression of bone marrow activity, decreased erythropoiesis, shortened erythrocyte lifespan, inflammatory sequestration of iron within bone marrow myeloid cells and loss of erythrocytes into the uterine lumen, leading to impaired hemoglobin synthesis in pyometra-affected bitches (Hagman et al. (2014) [10] ; Samantha et al., 2018 [22] ; Grimes and Fry, 2014 [7] ; Unnikrishnan et al., 2020 [28] and Chitra, 2025 [2] ). The mean TLC (×10³/µL) was elevated on the day of presentation in both treatment groups, indicating leucocytosis (Table 1). Similar findings in pyometra-affected bitches were reported by Demeli et al. (2023) [3] , Chitra (2025) [2] , Pitroda et al. (2025) [18] and Suresh et al. (2025) [27] . The leucocytosis observed in the present study might be attributed to inflammatory leukogram changes associated with intensified bone marrow response, immunological stress, and diffuse suppurative uterine inflammation in response to infection (Sevelius et al., 1990 [24] ; Kustritz, 2005 [15] ; Verstegen et al., 2008 [29] ; Unnikrishnan et al., 2020 [28] and Chitra, 2025 [2] ). The mean neutrophil count was elevated, while lymphocyte count was reduced on the day of presentation in both treatment groups (Table 1). Similar findings in pyometraaffected bitches were reported by Anusha et al. (2023) [1] , Chitra (2025) [2] , Pitroda et al. (2025) [18] , and Suresh et al. (2025) [27] . The neutrophilia observed might be attributed to increased granulopoiesis stimulated by the chemotactic effect of purulent uterine exudates, whereas lymphocytopenia could be associated with endotoxemia-induced immunosuppression and disease severity (Singh et al., 2006 [25] ; Prasad et al., 2017 [19] and Unnikrishnan et al., 2020 [28] ). The mean monocyte values remained within the normal physiological range throughout the study period, which was in accordance with the findings of Unnikrishnan et al. (2020) [28] and Konjeti (2021) [13] . Values with different lowercase superscripts (a,b) within rows denote significant differences across the days.

Values with different uppercase superscripts (A,B) within columns denote significant differences between the groups. Significant association ( * p<0.05; ** p<0.01)

The total protein values (g/dl) remained within the normal physiological range throughout the study period (Table 2), which was in accordance with the findings of Nayana et al.

(2021) [16] , Janković et al. (2022) [12] and Kumar, (2023) [14] . The mean albumin concentration (g/dl) gradually increased during the treatment period, whereas globulin concentration was elevated on the day of presentation. Similar findings in pyometra-affected bitches were reported by Renukaradhya 2011 [21] , Demeli et al., 2023 [3] , Kumar 2023 [14] and Paudel et al., 2023 [17] . Hypoalbuminemia in pyometra affected bitches might be attributed to loss of albumin through damaged kidneys while hyperglobulinemia could be associated with acute phase inflammatory response and enhanced antibody production as a defensive response against infection, as opined by Hagman (2014) [10] and Kumar (2023) [14] . The ALT, AST and ALP values (IU/L) recorded during the study period remained within the normal physiological range. Similar findings in pyometra-affected bitches were reported by dos Anjos et al. (2021) [4] , Renukaradhya (2011) [21] , Kumar (2023) [14] and Gangavati (2023) [6] . The mean BUN (mg/dl) and creatinine concentrations (mg/dl) remained within the normal physiological range throughout the study period. Similar findings in pyometra-affected bitches were reported by Hagman et al. (2009) [8] , Nayana et al. (2021) [16] , and Kumar (2023) [14] . Verstegen et al. (2008) [29] opined that BUN levels are usually not elevated unless pre-renal azotemia develops secondary to dehydration, while normal creatinine values indicate preserved renal function in affected bitches.

Conclusion

The present study demonstrated that pyometra in bitches was associated with significant hematological and biochemical alterations indicative of systemic inflammation and infection. Medical management resulted in progressive improvement in hematological parameters, evidenced by increased hemoglobin, total erythrocyte count, packed cell volume, and lymphocyte count, along with decreased total leukocyte count and neutrophil percentage during the treatment period. Biochemical alterations such as hypoalbuminemia and hyperglobulinemia also showed gradual improvement following therapy, whereas liver and renal function parameters remained within normal physiological limits throughout the study period. The findings suggest that periodic hematobiochemical evaluation is a valuable tool for assessing disease severity, systemic involvement, and therapeutic response in pyometra-affected bitches undergoing medical management.

Acknowledgement

AcknowledgmentThe authors gratefully acknowledge Sri Venkateswara Veterinary University (SVVU) for providing the necessary facilities. This study forms a part of the M.V.Sc. research work submitted to Sri Venkateswara Veterinary University (SVVU).

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