A Differential Diagnosis for Lyme Disease in Dogs

by lmatthews on April 5, 2013

confused dog differential diagnosis lyme disease

What's up dog?

What else could be causing symptoms that look like Lyme disease in your dog? Borreliosis has been called the ‘great mimic’ and this holds true even when we’re talking about a dog infected with Lyme disease. Arthritis, weird behavior, excessive thirst, lack of appetite, disinclination to play and even aggression could all be signs of Lyme disease in dogs but what if something else is behind these and your dog is misdiagnosed?

Before upping the dose of an antibiotic that does not seem to be clearing up symptoms, ask if your vet has considered the following conditions that can cause neurological, musculoskeletal and cardiovascular symptoms in dogs:


  • Ehrlichiosis
  • Babesiosis
  • Anaplasmosis
  • Kidney failure
  • Arthritis
  • Neosporosis
  • Canine thyroid disease
  • Canine distemper
  • Syringomyelia
  • Cauda equina syndrome
  • Thrombocytopenia
  • Haemolytic anaemia
  • Tick paralysis
  • Rocky Mountain Spotted Fever

Fatal Heart Attacks from Lyme Disease Treatment

Ticks carrying a variety of bacteria and viruses and some of them are not able to be eradicated using Lyme disease antibiotics such as doxycycline and azithromycin. Additionally, it may be that using Zithromax to treat what look like symptoms of Lyme disease in a dog could lead to death from heart failure, as recent research found a link between Zithromax and fatal heart attacks. Lyme carditis can itself weaken the heart so treating a dog with existing cardiovascular issues with an antibiotic such as this may do more harm than good. Some dog breeds are also more prone to heart problems, whereas others are thought more prone to kidney issues (Labrador retrievers, golden retrievers and Bernese Mountain dogs). Other dogs, such as Border Collies are unable to have some types of medication because these can cross the blood-brain barrier in such breeds (leading to the mantra of ‘white feet don’t treat’).

Early Treatment for Dogs with Lyme Disease

Lyme disease in dogs may have become more common in the US in recent years, especially in the upper Midwestern states, the Atlantic seaboard and in the Pacific Coastal states but there are still a whole host of other illnesses that should be ruled out when diagnosing a dog with Lyme disease (just as with human patients). Even a dog that has had Lyme disease and been treated successfully may be reinfected or may develop an entirely unrelated condition at a later date. Either way, it is essential that symptoms are not ignored and are not simply lumped in with a previous infection and left untreated until it is too late to really do any good.

Prevention of Lyme Disease in Your Dog

High tick season is almost upon us, our dogs will be rolling happily in the grass and the carefree days of summer may lead us to forget to carry out tick checks for all family members, two-legged and otherwise. Tick checks are still the best way to prevent transmission of Lyme disease bacteria from a tick bite on a dog, although some tick and flea prevention treatments can reduce the likelihood of such bites occurring. With such potentially fatal symptoms of Lyme disease in dogs it is vital to catch the infection early and seek veterinary care so do not delay if you suspect your dog is sick.

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