(case report)
Dr. Plamen M. Kirov, DVM, MVSc, MSc
Timisoara -Romania, and Sofia-Bulgaria
Introduction
Hematuria describes a condition in which is observed presence of blood in the urine. It could be a result of diseases of the urinary tract – kidney, ureter, urinary bladder, urethra; or by diseases of the genital tract – prostate, penis, prepuce, uterus, vagina, vestibule. It can be classified as: macroscopic (visible to the naked eye), or microscopic (increased number of RBC in the urine, observed during microscopic examination). In general, hematuria can be a result of multiple reasons, as follows [1]:
- Urinary tract origin
- Trauma
- Urolithiasis
- Neoplasia
- Inflammations (UTI, etc.)
- Parasites (Dioctophyma renale)
- Coagulopathy (Warfarin intoxications, etc.)
- Renal infarction
- Renal pelvic hematoma
- Vascular malformations
- Kidney polycystic disease
- Genital tract origin
- Trauma, Neoplastic or Inflammatory diseases of the genital tract
- Estrus
- Subinvolution of placental sites
For Idiopathic Renal Hematuria, we speak when the origin of RBC in the urine cannot be associated with any of the above-enumerated reasons and is of a renal origin. It is a very rare condition, which occurs in middle and big-sized young dogs (younger than 5 years of age), occasionally has been observed in older dogs and cats. Microscopic IRH is found by incidence during urine microscopic exams when macroscopic one is observed by the owners and described as unusual darker coloration of the urine. The condition is mostly unilateral and can be periodic – with a period of no bleeding. Since there is a release of RBC into the urine, anemia can be present in ranges from none to severe. Further, we will take a look and discuss the available treatment options.
Clinical case
The dog was brought to me by his owner, who observed “Cola-like” coloration of the urine in the last 2-3 days. According to the owner’s description, there are no changes of the dog’s behavior and, according to him, the micturition is normal and does not cause discomfort.
The patient:
- 3-year-old male mongrel dog
- 25 kg BW, normal body score
- Neutered when he was 8 months of age
- Vaccinations up to date and according to the protocol
- Living indoors
- No data for traumas
- No medications or treatments in the last 6 months
Physical examination
During the physical examination, no abnormalities were observed, body temperature, heart and respiratory rate, and blood pressure were in the normal ranges. No any tegument abnormalities or signs of traumas. Dog temperament was relaxed and friendly.
Clinical diagnostic tests
The CBC was normal, with an RBC count near the left border reference value. Tests for Babesiosis and Lyme disease were negative. A sterile probe of urine was collected by US-guided cystocentesis and examined. Urine-specific gravity was slightly elevated, presence of erythrocyte was confirmed by microscopic examination, microbiological culture was negative. Pigmenturia was excluded after centrifugation of the urine sample, which resulted in a clear separation between RBC (collected at the bottom of the test tube) and urine (supernatant).
The performed x-ray did not reveal any abnormalities (uroliths, tumors). The ultrasound examination did not result in any abnormalities in the urogenital tract – renal parenchyma was with normal structure.
Idiopathic Renal Hematuria was diagnosed by exclusion as a result of performed test procedures and obtained results.
Additional information about the diagnostic approaches for hematuria in dogs and cats can be found in [2]
Treatment options
For treating Idiopathic Renal Hematuria we have few options available, we could differentiate as:
- Invasive. Surgical cauterization of both ureters before the urinary bladder, and observing which kidney is the bleeding one, sclerotization of the kidney with povidone-iodine and silver nitrate [3][4] [5]. This method can be used and for bilateral hematuria. For cases with unilateral bleeding leading to severe anemia, ureteronephrectomy is recommended [1]
Since the dog doesn’t present anemia and invasive methods are more complex for performance and maintenance, I have directed my decision towards a non-invasive treatment option.
- Non-invasive. It was described that IRH results from elevated blood pressure inside the glomerular arterioles leading to their higher permeability for RBC. This was observed by multiple studies and reports and the effect of ACE2 inhibitors, especially Benazepril, over the arterioles in the renal glomerulus was demonstrated [6] [7] [8]. In addition, during my studies in FMV-Timisoara, I had the opportunity to observe the treatment of a hunting dog with IRH, using Benazepril with good results (Dr. Doru Morar, FMV-Timisoara).
The dog was treated with Benazepril in dose 0.40mg/kg per os every 24h. In the following days was observed visible reduction of the hematuria – by the owner’s account, urine coloration became normal. Repeated urinalysis revealed the persistent microscopic presence of RBC with a tendency of reduction during the time. Blood pressure was normal and without indications for hypotension during treatment.
Conclusion
Dogs diagnosed with IRH with absent to mild anemia can profit from treatment plan with ACE2 inhibitors – surgical methods are not widely available, are expensive, require hospitalization of the animals, and nephrectomy deteriorates the quality of life for young animals (in cases the IRH becomes bilateral this can lead to a negative outcome for the patient).
