Presenter: David Walker B.Vet.Med (Hons) DipACVIM DipECVIM-CA MRCVS, Anderson Moores
Alabama Rot or Cutaneous and Renal Glomerular Vasculopathy (CRGV) was a disease which only got a brief mention during my undergraduate training. It was cited as a rare disease mostly confined to greyhounds and this was aptly demonstrated by the last case of confirmed CRGV being seen in a greyhound back in the early 2000s. That was until three years ago where between December 2012 and February 2013 there were four cases, all from the New Forest, referred to Anderson Moores with acute kidney injury (AKI) having developed skin lesions several days earlier. Unfortunately all these cases succumbed to their disease and one owner consented to a post mortem where a thrombotic microangiopathy (TMA) affecting the small vessels of the skin and kidney was noted on histology, a finding consistent with a diagnosis of CRGV.
Since December 2012 there have been 56 confirmed cases of CRGV reported from all over the country and David Walker from Anderson Moores, who is responsible for the first group of referred cases, led last week’s fascinating webinar discussing this condition which appears to be on the rise.
David analysed the case information from thirty of the fifty six confirmed cases to give some useful advice on signs to look out for when considering CRGV as a differential diagnosis. David was keen to emphasize the aetiology of this disease is not known but it does appear to be seasonal with most cases being seen over winter and spring. It is no longer a disease just of greyhounds, now affecting a wide range of breeds and sizes of dogs. The average age of the thirty dogs analysed was 5 years but ranged between 1-12 years. The distribution of this disease initially seemed biased towards Hampshire but David believes this was probably awareness driven, as over time the proportion of cases in Hampshire has reduced and CRGV now seems to be a disease with a nationwide distribution.
Clinically most cases of CRGV first present with skin lesions usually on the distal limbs but lesions can also affect the muzzle, ventrum and even the tongue. The skin lesions can be very subtle and are usually attributed to bites, stings or focal dermatitis at initial consultation. However they can also develop into more significant looking lesions which can be ulcerated and oedematous. The disease then progresses over a period of around four days where dogs go on to develop acute kidney injury. Clinical pathology can also be a useful tool in deciphering if a dog with a skin lesion could in fact be suffering from CRGV. Fifteen out of the thirty dogs were thrombocytopaenic at initial presentation with seven out of thirty dogs being anaemic. Twenty six out of thirty dogs were also azotaemic at presentation, an unusual finding in dogs with common skin diseases.
Post mortem and histological findings confirmed the diagnosis of CRGV in all 56 dogs discussed earlier but David also cited a further eight dogs who survived. Although CRGV was not confirmed in these cases there was a high index of suspicion these dogs were suffering from CRGV. However there appeared to be no specific finding such as age, breed, sex and clinical signs which differentiated the dogs who survived from the dogs that died.
David discussed many aspects of CRGV in much greater depth even comparing it to some similar conditions in humans. Clearly this is a disease which needs considerably more research and by raising awareness to vets all over the country, we can identify more cases of CRGV and gather further data so we are better prepared to prevent, diagnose and manage these cases. ‘The Webinar Vet’ has provided an important platform on which awareness about ‘Alabama Rot’ can be raised and I urge you to watch this veterinary webinar to find out more about this devastating disease.
The Stethoscope (MRCVS)