Feline Hemoplasmosis (Feline Infectious Anemia): Flea Transmission, PCR Diagnosis & Treatment

1. Etiological Agents and Transmission Dynamics

Feline hemoplasmas are specialized unculturable epierythrocytic bacteria. Three species infect domestic cats:

• **Mycoplasma haemofelis:** The most pathogenic and virulent species, responsible for severe acute hemolytic crises in healthy cats.
• **Candidatus Mycoplasma haemominutum:** Highly prevalent but generally causes mild or subclinical anemia unless co-existing with FeLV or FIV retroviral infections.
• **Candidatus Mycoplasma turicensis:** Moderately pathogenic.

Transmission occurs primarily via cat flea infestations, cat bite wounds among intact roaming toms, and blood transfusions from unscreened donor cats.

---

2. Clinical Signs: Recognizing Acute Hemolytic Crisis

Symptoms characteristically wax and wane in cycles corresponding to parasitemic waves in peripheral blood:

• Profound Mucosal Pallor: Gums, tongue, and conjunctiva turn ghostly white or pale porcelain.
• Icterus (Jaundice): Severe intravascular or extravascular hemolysis releases overwhelming amounts of bilirubin, tinting sclera, pinnae, and oral mucosa yellow.
• Tachypnea and Respiratory Distress: The cat breathes rapidly and shallowly to compensate for depleted oxygen-carrying capacity (hematocrits dropping below 15%).
• Splenomegaly & Pyrexia: Marked splenic enlargement on palpation accompanied by cyclical fever spikes up to 40.5 °C (105 °F).
• Pica: Compulsive licking or ingestion of non-food materials such as clay cat litter or concrete.

---

3. Accurate In-Clinic Diagnostic Protocol

A targeted diagnostic workup is critical to ensure timely medical therapy:

1. Complete Blood Count (CBC): Reveals severe macrocytic normochromic or hypochromic anemia with strong reticulocytosis (regenerative response) unless complicated by marrow disease.
2. Peripheral Blood Smear Examination: Small basophilic cocci, rings, or chains may be seen on erythrocytes; however, EDTA anticoagulants cause organisms to dissociate within hours, yielding false negatives in up to 50% of cases.
3. Real-Time Polymerase Chain Reaction (qPCR): The diagnostic gold standard, offering near-100% sensitivity to identify and quantify specific hemoplasma species.

---

4. Targeted Antimicrobial and Immunosuppressive Therapy

Successful treatment requires eliminating both the bacterial burden and the secondary immune attack:

• Antimicrobial Protocol: Doxycycline (10 mg/kg orally once daily or 5 mg/kg twice daily for 14–28 days) or veterinary fluoroquinolones such as pradofloxacin (Veraflox). Critical warning: Doxycycline tablets must always be flushed with a liquid chaser or wet food to prevent esophageal lodging and fatal strictures.
• Immunosuppressive Corticosteroids: Oral prednisolone (1–2 mg/kg/day) is administered initially to stop the spleen from clearing antibody-coated red blood cells.
• Emergency Blood Transfusion: Indicated when the packed cell volume (PCV) drops below 12–14% with signs of cardiovascular decompensation, requiring cross-matching and blood typing (A, B, or AB).

---

5. Chronic Carrier State and Household Prevention

• Even with successful clinical cure, many treated cats remain asymptomatic subclinical carriers harboring low bacterial reservoirs.
• Year-Round Flea Prevention: Consistent administration of veterinary-grade flea preventatives across all household pets is the single most effective barrier against infection.

---

Scientific Sources and References

• Tasker, S. (2010). Haemotropic mycoplasmas: what's the real story in cats? Journal of Feline Medicine and Surgery, 12(5), 369-382.
• Messick, J. B. (2004). Hemotrophic mycoplasmas (hemoplasmas): a review. Animal Health Research Reviews, 5(1), 17-34.
• Lappin, M. R., et al. (2020). Update on feline hemotropic mycoplasmas: Diagnosis, treatment, and prevention. Journal of Feline Medicine and Surgery, 22(4), 312-321.
• Dodds, W. J. (2005). Feline hemobartonellosis and immune-mediated hemolytic anemia. Veterinary Clinics: Small Animal Practice, 35(1), 189-204.