CONDITION

Alabama Rot (CRGV)

Alabama rot — formally called cutaneous and renal glomerular vasculopathy, or CRGV — is a condition in which small blood vessels in the skin and sometimes the kidneys become damaged and inflamed. The cause remains unknown. It is rare: typically fewer than 50 confirmed cases are recorded each year in the UK, though the condition attracts significant attention because of its severity and the uncertainty surrounding it. Owners most often notice unexplained skin lesions, particularly on the legs or paws — areas that can appear red, ulcerated, or swollen without an obvious injury. In some animals, kidney function may also be affected, though not all cases progress in this way. The pattern and progression can vary, and the condition can resemble other causes of skin wounds or illness. This page explores what is observed in affected animals, what may be happening beneath the skin, how the condition is investigated, and the approaches that may be considered when CRGV is suspected. It also examines what is currently understood — and not yet understood — about how and why it occurs.

Why this matters now

Alabama rot cases in the UK cluster predominantly between November and May, with wet, muddy walking conditions appearing to be a common factor. The condition can affect dogs of any breed, age, or size, though certain areas report higher case numbers. The cause remains unidentified despite ongoing research.

The condition typically begins with unexplained skin lesions, often on the legs, paws, or face. These may initially resemble cuts, stings, or other minor injuries. In some dogs, the disease progresses over days to affect the kidneys, causing acute kidney injury. This progression does not occur in all dogs with suspected skin lesions, but when it does, it can be severe.

Signals & patterns

Early signals

Unexplained skin sores

Lesions typically appear as red, ulcerated areas, often on the lower legs, paws, chest, or muzzle without known trauma.

Swelling around lesions

The tissue surrounding skin sores may appear puffy or oedematous.

Licking at affected areas

Dogs may show attention to developing lesions before they become obviously visible.

Recent muddy walks

Many affected dogs have a history of walking in wet, muddy woodland areas in the preceding days.

Later signals

Reduced appetite

Declining interest in food may indicate systemic effects as the condition progresses.

Lethargy

Generalised weakness and reduced activity can accompany kidney involvement.

Vomiting

Nausea and vomiting may develop as kidney function becomes impaired.

Reduced urination

Decreased urine production suggests developing acute kidney injury.

Click to read about the biological mechanisms

How this is usually investigated

Investigation begins with careful examination of the skin lesions and a detailed account of recent activity, including where the dog has been walked. Because the condition is rare and the early skin changes can resemble many other causes of wounds or ulcers, the clinical picture develops over time. Blood and urine tests help identify whether kidney involvement has occurred, which is the key prognostic factor.

Physical examination

Purpose: The appearance and distribution of skin lesions offer important clues. Lesions in Alabama rot often appear on the lower legs, paws, or face, and tend to be well-demarcated ulcers with surrounding redness or swelling.
Considerations: The skin changes can look similar to burns, insect stings, or trauma in the early stages. Physical examination alone cannot confirm the diagnosis, as there is no definitive test for CRGV.

Chemistry panel

Purpose: Measures kidney function markers, particularly creatinine and urea. Rising levels indicate acute kidney injury, which may develop several days after the skin lesions appear.
Considerations: Early results may be normal even in dogs that will later develop kidney damage. Serial testing over several days is often needed to track progression.

Complete blood count

Purpose: May reveal anaemia or abnormalities in platelet numbers, which can occur in thrombotic microangiopathy. Changes in red blood cell shape can sometimes be seen.
Considerations: Results are often non-specific and many dogs with CRGV have normal blood counts. The test helps rule out other causes of illness rather than confirming Alabama rot.

Urinalysis with sediment

Purpose: Detects protein in the urine and may reveal blood or casts, reflecting kidney damage at the glomerular level. Protein loss can be an early sign of renal involvement.
Considerations: Urine changes can occur with many kidney conditions. The pattern may be suggestive but is not unique to CRGV.

Histopathology

Purpose: Biopsy of skin lesions can reveal the characteristic thrombotic microangiopathy, showing damaged blood vessels and clot formation in small capillaries. This is the closest available test to confirming the condition.
Considerations: Biopsy requires anaesthesia and the lesions may be in locations that heal poorly. The histological changes can overlap with other vascular diseases, and a biopsy is not always pursued if kidney function is the primary concern.

Options & trade-offs

Management centres on supporting kidney function and preventing further deterioration, as there is no specific treatment that targets the underlying cause. The approach varies depending on whether kidney injury has developed and how severe it is. Some dogs with skin lesions alone recover without intervention, while others require intensive hospital care.

Intravenous fluid therapy

Fluids are given through a vein to support kidney perfusion, maintain hydration, and help the kidneys eliminate waste products. This is the mainstay of treatment for dogs showing signs of acute kidney injury. The rate and composition are adjusted based on blood tests and urine output.

Trade-offs: Requires hospitalisation, often for several days or longer. Some dogs respond well and kidney function recovers; in others, damage progresses despite treatment. The cost and emotional impact of prolonged intensive care can be substantial.

Wound care and pain management

Skin lesions may be cleaned, covered, or left to heal depending on their location and severity. Pain relief is provided as needed. Some lesions heal spontaneously, while others may require ongoing attention or surgical debridement if tissue is necrotic.

Trade-offs: Wound healing can be slow and the appearance may be distressing. Pain levels vary between individuals. Wound care alone does not address kidney involvement if it occurs.

Immunosuppressive or anticoagulant therapy

Some clinicians have used drugs such as corticosteroids, plasma exchange, or medications to reduce clotting in an attempt to interrupt the disease process. The rationale is based on the thrombotic microangiopathy mechanism, though no controlled studies have demonstrated benefit.

Trade-offs: Evidence for efficacy is limited and largely anecdotal. These treatments carry their own risks, including immune suppression or bleeding. The rarity of the condition makes it difficult to assess outcomes rigorously.

Monitoring without intervention

Dogs with skin lesions but normal kidney function may be monitored closely with repeat blood and urine tests over several days. If kidney parameters remain stable, intensive treatment may not be needed. The focus shifts to wound healing and observation.

Trade-offs: This approach relies on frequent reassessment to detect early kidney changes. Progression can be rapid in some cases, and delayed intervention may reduce the chance of recovery. It suits dogs with mild, localised lesions and stable clinical signs.

Common misconceptions

Misconception:

"Alabama rot is becoming more common and poses a widespread risk to dogs in the UK."

Reality:

The condition remains rare, with typically fewer than fifty confirmed cases annually in the UK. While the exact number fluctuates year to year and some areas report clusters, the overall incidence is very low relative to the dog population. The prominence of the condition in media and owner discussion often reflects concern rather than frequency.

Misconception:

"Washing a dog's legs after muddy walks will prevent Alabama rot."

Reality:

No preventive measure has been shown to reduce risk, as the cause of the condition is unknown. Rinsing muddy paws is a reasonable hygiene practice for many reasons, but there is no evidence it influences the likelihood of developing CRGV. The association with wet, muddy conditions is observational and the specific trigger has not been identified.

Related conditions

Chronic Kidney Disease in Dogs

Alabama rot causes acute kidney injury through damage to the small blood vessels in the kidneys, while chronic kidney disease involves progressive decline in kidney function over a much longer timeframe. Both conditions can affect waste filtration and fluid balance, though through different mechanisms and time courses.

Chronic Kidney Disease in Cats

The renal damage seen in Alabama rot shares some overlapping features with chronic kidney disease in cats, particularly in terms of glomerular involvement and reduced filtration capacity. However, Alabama rot typically presents acutely in dogs, whereas chronic kidney disease in cats develops over months to years.

Atopic Dermatitis in Dogs

Both Alabama rot and atopic dermatitis can cause skin lesions in dogs, though the underlying mechanisms differ substantially—vasculopathy and tissue death in Alabama rot versus immune-mediated inflammation in atopic dermatitis. The skin changes in Alabama rot tend to be more focal and ulcerative, often affecting the limbs.

Lymphoma in Dogs

Lymphoma and Alabama rot both involve the immune and inflammatory systems, though lymphoma is a cancer of lymphatic tissue while Alabama rot is a vasculopathy. In some cases, skin lesions or systemic illness may prompt consideration of both conditions during the diagnostic process.

Pneumonia

Pneumonia and Alabama rot can both present with signs of systemic illness and reduced activity, though pneumonia primarily affects the respiratory system through infection or inflammation of the lungs. In advanced cases of Alabama rot, reduced kidney function and general unwellness may occur alongside the characteristic skin lesions.

Understanding the early signs of skin lesions and the timeframe in which kidney changes may develop can help inform decisions about monitoring and when to seek reassessment. The broader context of immune-mediated and vascular conditions may offer useful perspective on how the body's systems can be affected by processes that disrupt normal blood flow. Because the condition is rare and the outcome variable, conversations about prognosis and the scope of treatment can be valuable as the clinical picture unfolds.

Last reviewed: 24 April 2026 · Dr Alastair Greenway MRCVS