Wednesday, April 18, 2012

The Veterinary Journey of a Much Loved Dog.

             18 month adventure

Allow me to introduce Mattie.... a 10 year old, neutered male, Maltese Yorkshire Terrier mix... a whopping 10 pounds of wonder.

Mattie initially came to us with a sore foot. In veterinary normal terms an infected, inflamed sore area between the toes, also affecting the nail bed. His owner reported he had suffered from this on many occasions in the past.

During his general examination it was noted that he had:

  • a pot bellied appearance with a distended abdomen
  • a large liver with edges extending beyond his ribs
  • a thin hair coat especially along his sides
  • mild-moderate dental calculus
  • restricted range of motion in his hind limbs, abnormal patellar (knee cap) movement on both hind legs and joint changes in the left knee
His general appearance, and recurrent skin issues, gave us concern that he may have a condition called "Canine Cushings" that results in excess circulating cortisol (steroid) and associated complications.

Mattie was about to begin his journey! 

Blood and urine tests were run. He was given antibiotics for his sore foot and his owner was instructed to clean his foot daily with an antiseptic soap. The tests revealed elevated liver enzymes, a low urine concentration, excess protein in his urine and a high urine protein/creatinine ratio without specific kidney disease. These test results were very suspicious for Cushings.

Initial testing was done to rule in/out Cushings. There are two common tests for this:
  • a Low Dose Dexamethasone Suppression Test
  • an ACTH Stimulation test
The former test was run....and, to our amazement, it was normal!

Given the excess protein in his urine, his blood pressure level was checked. It was high. Mattie was put on medication to help manage both his elevated blood pressure and the protein in his urine.

For a few months Mattie went along without further incident. On his medication his blood pressure returned to normal.

Then Mattie came in lame behind.... he was hurting. We knew he had chronic issues in his hind limbs and suspected these issues were now causing him to be painful. Observation of how he was moving, and an examination, confirmed his hind end was troubling him. Radiographs (X-rays) were taken and showed signs of osteoarthritis and inflammation in both of his knees.  These we not the only changes noted. His liver was indeed very large and he had a calcified stone just in front of his os penis. (Yes...male dogs do have a bone in their penis!) Despite this finding his owner assured us he was having no problem urinating.

Treatment options, both surgical and medical, were discussed with his owner. As the urethral stone was not causing any problems at the moment his owner opted for a "wait and see" approach. Given his age, the chronicity of his problems and his medical issues a more conservative medical management  route was chosen for his lameness, rather than the more aggressive surgical option for correction of his patellar and cruciate ligament abnormalities. Mattie was put on pain medication and a joint protectant. He resumed his normal activity level and continued to pass urine without difficulty. Mattie felt well on his medication.

Periodically Mattie had his urine checked to monitor the protein level. Despite an increase in his medication, his protein/creatinine ratio was increasing and his blood pressure was high again. We were concerned. Bloods were run and his liver enzymes were higher than before. Mattie had something going on and we had to determine what it was.

The possibility of Cushings remained a concern. This time we ran an ACTH Stimulation Test. It was positive! Once a dog is determined to have Cushings the physical origin of the problem must be determined as treatment options differ depending on the origin of the problem. To make a long story short, the problem can originate in either the pituitary gland in the head, or the adrenal gland in the abdomen. Medication is used to manage Pituitary Cushings and surgery is the treatment for Adrenal Cushings. In a normal dog the pituitary secretes a substance that activates the adrenal to produce cortisol. When adequate amounts of cortisol are circulating in the blood the pituitary does not ask the adrenal to make more; when levels are lower the pituitary gets active, and signals the adrenal to produce more. This is type of control is called a negative feed back loop. Thus either the pituitary (the general) or the adrenal (the manufacturer) can be out of control. In order to determine where the problem is one can do a blood test (High Dose Dexamethasone Suppression Test) and an abdominal ultrasound. If the blood test is positive the problem is the pituitary. If it is negative it is likely the adrenal that has gone wrong and an ultrasound can confirm this. Mattie's problem was his pituitaryNow there is a definitive diagnosis  and treatment can be started. Treatment for Cushings is tricky and requires medication to control the adrenal production of cortisol. Clinical signs, and blood test results, help determine the correct dose of the required medication. In Mattie's case it took quite a while to fine tune his oral medication to fit his specific needs. Cushings is controlled/managed, not cured, so life long medication is required. His owner, WBVC and Mattie are a team ... all are invested in keeping his problem well controlled.

Unfortunately, Mattie's journey had not ended!

His dental disease had rapidly worsened while his Cushings disease was not fully under control! Mattie required major dental work. Under general anaesthesia he had a dental prophy, to remove his plaque and calculus, and his mouth was charted. Gross abnormalities were noted and it was determined he required dental radiographs. At WBVC these are done with a special dental x ray unit using DR digital technology. The x rays showed extensive apical root abscessation and bone resorption. Mattie required several extractions.

 Even though he was under general anaesthesia, regional local anaesthetic blocks were used in order to avoid an excessive depth of general anaesthetic, and to aleviate post operative pain. Teeth with more than one root are cut into sections with a high speed dental drill before the roots can be removed. Once the root is removed the empty socket is cleaned, and packed with special material, to help healing. The tissue around the the tooth is surgically fashioned to make a flap that is used to close over the defect left after a root extraction. Mattie had seven teeth extracted! He did very well and went home with pain medication, and anitbiotics. A few days after his dental surgery his owner said he was running around like a puppy...he hadn't felt so well in years!

However, the issue of the urethral stone had been left unaddressed and, unsurprisingly, Mattie started to have difficulty passing his urine! He could still pass urine, but it is a pitiful stream. We are able to pass a small catheter and get a urine sample from the bladder. Calcium oxalate crystals were in his urine.. his urethral stone would likely be Calcium oxalate as well. The stone needed to be removed and his owner did not want him to undergo surgery. Fortunately, thanks to modern technology, there was a solution for Mattie's problem....laser lithotripsy! Under general anaesthesia a flexible ureteroscope was passed into the penile urethra. The stone was firmly adhered to the lining of the urethra. Once directly visualized the stone was fragmented in the urethra using laser lithotripsy! The pieces were removed using a basket attachment on the tiny endoscope. No more more urinary problem. Unfortunately Calcium oxalate stones tend to recur over time. Specially formulated diets do help reduce the incidence of recurrence.

Our Mattie continues to do well...we hope this medical journey is at an end!

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