A 7 year old male Cayman Islands Iguana presented to my clinic with a very experienced and knowledgeable owner who has kept various Iguana species for many years. This specimen was usually quite aggressive and active but for the previous few days had been lethargic, quiet and non responsive to the owner during routine husbandry tasks and feeding. In fact he had refused to eat anything for 2-3 days, so the owner knew something must be seriously wrong.
When I examined him he had a small abrasion on his chin, but other than that there were no external abnormalities and he looked outwardly like a very healthy lizard. However, when we restrained him for closer examination I managed to palpate a large firm mass in his ventral abdomen which was definitely abnormal. I gave him some gaseous anaesthesia and took an X-ray to try to find out what this mass was.
The X-ray revealed a large, round, irregular, solid mineralised opacity in the mid abdomen cranial to the pelvis. The margins of the mass were somewhat ‘fluffy’ or sclerotic however so it did not have the typical appearance of a smooth mineralised bladder stone or urolith, although the shape and location was consistent with this possibility. However, due to the strange appearance and the fact that certain tumours can become calcified, I was not 100% certain on a firm diagnosis of a bladder stone or tumour without further investigation.
After some discussion with the owner, it was decided to perform an exploratory surgery and treat according to what I found if possible. The owner had raised this magnificent animal from a baby and was not willing to give up on him without a firm diagnosis and exhausting all possible treatment options.
I proceeded to anaesthetise him with an injectable sedative and analgesic drug combination, and maintained him on gaseous anaesthesia after admitting him to hospital and getting him warmed up to allow him to metabolise the drugs effectively. I also administered some further long lasting pain relief to keep him comfortable in the post-operative period. Upon opening his abdomen, I discovered that the mass was in fact a very enlarged bladder, but luckily it was not a tumour.
Rather, there was a solid mass occupying the entire lumen or space contained by the bladder walls, but it was not attached. Strangely the mass was friable or soft when squeezed through the bladder wall. I performed a cystotomy incision through the bladder wall which revealed the surface of a large abscess; the typical caseous or solid, cheese-like pus material that reptiles produce was visible on the surface at least. Some of this flaked away to reveal a calcified urolith or bladder stone just below the surface of the abscess. I had to extend the incision to remove a large stone from within the centre of the infectious hard pus capsule, before painstakingly removing this pus piece by piece from the depths of the large distended and inflamed bladder.
Once I had removed all solid material I carefully flushed the bladder to remove as much infected material as I could, before closing the bladder incision with a two layer inverting suture pattern to prevent leakage into the abdominal or more correctly termed coelomic cavity. Reptiles do not possess a muscular diaphragm separating the thorax (chest) from the abdomen like in mammals, so the common single internal cavity containing all the organs is called a coelom (pronounced ‘see-loam’). I then flushed this coelomic cavity to again minimise any contamination by the infection within the bladder. I administered antibiotics having taken a swab for culture so that if an infection occurred post-operatively I would know what next antibiotic to treat it successfully with. I gave him subcutaneous warm fluids both to hydrate him after surgery and keep his temperature up so he would recover quicker, along with keeping him warm throughout the operation with a heat mat and pads surrounding him. I was worried that his kidneys could be affected by pressure from the blocked bladder as well as ascending or tracking infection, so needed to ensure he was maximally hydrated by flushing his kidneys through with fluids.
Once I had flushed and was confident most infection had been removed, I closed the trapdoor type incision I had made to gain access to the lizard’s internal organs. He recovered slowly from his ordeal, as it was a long surgery and also having systemic infection he was somewhat debilitated.
The next day however he was back to his usual feisty self and went home to his capable owner with oral medications. He has thus far made a very good recovery and his owner reports that he is as aggressive as ever and tucking into plenty of food so seems to be doing very well. Certain dietary ingredients can predispose to urolith or stone formation, as well as genetic factors so the owner will be re-evaluating his diet to prevent risk of recurrence in future.