Hemotropic Mycoplasmosis (Feline Infectious Anemia)
Also known as: Feline Infectious Anemia, Hemobartonellosis (older name)
⚠ Emergency Warning Signs
Significant pale gums, weakness, or rapid breathing suggesting severe anemia warrant prompt veterinary evaluation.
Overview
Infection with Mycoplasma organisms that specifically attach to red blood cells, causing them to be destroyed by the body's own immune system in a process leading to anemia — genuinely notable for causing a specific, often diagnosable pattern of anemia, and for the fact that many cats can carry these organisms without significant symptoms until another stressor or illness triggers more significant disease.
Symptoms
- Lethargy
- Pale gums
- Decreased appetite
- Rapid breathing/heart rate
Causes
Infection with Mycoplasma haemofelis or related Mycoplasma species, which attach to the surface of red blood cells; this attachment triggers the body's immune system to destroy the affected cells, causing progressive anemia.
Risk Factors
Outdoor access (given transmission is believed to occur partly through flea bites and possibly cat fights/bites), and concurrent illness or immunocompromise (from FeLV, FIV, or other stressors) which can allow a previously subclinical infection to progress to more significant, symptomatic disease.
Transmission
Believed to be transmitted partly through flea bites, and potentially through cat bites/scratches during fighting, given how the organism can be present in blood; the exact relative importance of different transmission routes isn't entirely settled.
Incubation Period
Variable, developing over days to weeks following exposure.
Disease Stages & Progression
Many cats can carry this infection with minimal or no obvious symptoms, particularly if otherwise healthy; concurrent illness, immunocompromise, or other stress can allow the infection to progress to more significant anemia with associated symptoms.
Early Warning Signs
Lethargy, pale gums (reflecting developing anemia), and decreased appetite.
Advanced Symptoms
More significant anemia symptoms including pronounced pale gums, weakness, rapid breathing and heart rate (the body compensating for reduced oxygen-carrying capacity), and jaundice in some cases from red blood cell breakdown.
Diagnostic Methods
Complete blood count identifying anemia, combined with PCR testing (the more sensitive, reliable diagnostic approach) specifically identifying the causative Mycoplasma organism, confirms diagnosis.
Veterinary Examination Process
Assessment of gum color, heart rate, and overall condition reflecting the degree of anemia present.
Recommended Lab Tests
Complete blood count, blood smear examination, and PCR testing for definitive organism identification.
Diagnostic Imaging
Not primarily diagnostic; blood-based testing is directly relevant.
Blood Test Indicators
Complete blood count shows anemia; blood smear examination can sometimes directly identify the organisms attached to red blood cells, though this can be intermittent and easy to miss, making it a less reliably sensitive test than specific PCR testing, which is genuinely more sensitive and reliable for confirming this specific infection.
Biopsy / Histopathology
Not applicable to diagnosis of this condition.
Differential Diagnoses
Other causes of anemia including immune-mediated hemolytic anemia from other causes, and other infectious causes — PCR testing specifically confirms this diagnosis.
Home Monitoring Guidance
Not a substitute for veterinary evaluation of pale gums or other anemia symptoms — this needs proper diagnostic testing given the range of possible causes of anemia and the specific treatment this infection requires.
Veterinary Treatment Options
Antibiotic treatment (specific antibiotics effective against Mycoplasma organisms) addresses the infection directly; supportive care including blood transfusion for severe anemia may be needed in more significant cases, and addressing any concurrent illness or immunocompromising condition is also relevant given its role in disease severity.
Surgery Requirements
Not applicable.
Recovery Timeline
With appropriate antibiotic treatment, many cats show improvement within 1-2 weeks, though the organism may not be fully eliminated in all cases, with some cats potentially remaining carriers.
Possible Complications
Severe anemia requiring transfusion in significant cases, and the possibility of chronic carrier status even after treatment, with potential for recurrence if another stressor or illness occurs later.
Long-Term Management
Cats identified as carriers, or those with a history of significant infection, may benefit from monitoring during any future illness or stress, given the potential for the infection to become more clinically significant again under those circumstances.
Prevention
Flea prevention addresses one recognized transmission route; reducing cat fighting exposure through indoor living or supervised outdoor access addresses another potential transmission pathway. Consistent flea control (the primary transmission route) is the main practical prevention measure; testing and, if needed, treating a cat before or alongside a blood transfusion donor role is also relevant, since this organism can be transmitted through blood products from an infected but outwardly healthy carrier cat.
Vaccination Availability
No vaccine exists against this infection.
Prognosis
Good with appropriate antibiotic treatment for most cases, though severity and recovery can be influenced by any concurrent illness or immunocompromising condition present.
References
American Association of Feline Practitioners (AAFP); International Society for Companion Animal Infectious Diseases (ISCAID).
Medications Used
- Antibiotics specifically effective against Mycoplasma organisms
- Blood transfusion, for severe anemia
- Treatment for any concurrent underlying condition contributing to disease severity
Estimated Treatment Cost by Country
| Country | Estimated Cost Range | Notes |
|---|---|---|
| IN | 6,000–30,000 INR | |
| US | 600–3,000 USD | |
| UK | 500–2,500 GBP | |
| AU | 700–3,300 AUD | |
| JP | 90,000–380,000 JPY | |
| DE | 600–2,800 EUR | |
| BR | 1,200–5,800 BRL |
Frequently Asked Questions
My cat tested positive for this but seems healthy — do they need treatment?
This is genuinely worth discussing with your vet based on your cat's specific situation — some cats carry this organism without significant symptoms, and the decision about whether treatment is needed for an otherwise healthy, non-anemic cat with a positive test is individualized, though monitoring is reasonable given the potential for this to become more significant if another illness or stressor occurs.
Why did my vet want a PCR test instead of just looking at a blood smear?
Because the organisms can be present on red blood cells intermittently, meaning a blood smear examination can miss the infection even when it's genuinely present — PCR testing is considerably more sensitive and reliable for confirming this specific diagnosis, which is why it's generally preferred when this infection is a real diagnostic consideration.