Contributors: Andrew Gardiner, Joseph Harari, Carlos Pinto
Species: Feline | Classification: Diseases
Introduction Pathogenesis Diagnosis Treatment Outcomes Further Reading
Introduction
- Cause: usually ascending bacterial (Staphyloccus aureus, Escherichia coli, etc) infection through nipple during nursing (may be hematogenous or lymphogenous) - predisposed or exacerbated by trauma, unsanitary conditions.
- Signs: one or more mammary glands that are hot, eliciting signs of pain at touch or when trying to nurse, with purulent or blood-tinged mammary secretions; pyrexia, anorexia; kittens may be unable to feed - restless, cry, appear bloated or fail to thrive. At early stages of infection, it may be subclinical with only galactostasis of affected glands.
- Diagnosis: clinical signs; milk cytology showing degenerate neutrophils and bacteria; complete blood count may reveal neutrophilic leukocytosis with left shift.
- Treatment: systemic antibiotics, application of cold compresses to affected mammary glands; may need to wean kittens or feed artificially until infection controlled.
- Prognosis: good with prompt treatment.
Presenting Signs
- Lactating queen.
- Hot, mammary glands painful to touch.
- Purulent mammary secretions.
- Kittens unable to feed - restless, crying and may appear bloated
Pathogenesis
Etiology
- Escherichia coli Escherichia coli, Staphylococcus spp Staphylococcus spp , Streptococcus spp Streptococcus spp most common.
Predisposing Factors
General
- Queen and kittens under unsanitary conditions in nursing box.
- Ascending bacterial infection predisposed by:
- Constant nursing in queens with large litters.
- Secondary galactostasis in queens nursing small litters.
Pathophysiology
- Ascending bacterial infection through nipple during nursing.
- May be hematogenous or lymphogenous spread, eg metritis Acute metritis.
Diagnosis
Presenting Problems
- Young restless, not feeding, crying.
- Swollen mammary glands.
- Pyrexia Pyrexia: overview.
Client History
- Nursing female.
Clinical Signs
- Hot mammary glands painful to touch.
- Purulent mammary secretions.
- Kittens unable to feed - restless, cry, appear bloated.
- Pyrexia.
- Anorexia.
Diagnostic Investigation
Hematology
- Neutrophilic leukocytosis with left shift.
- Early/severe cases may show neutropenia with degenerative left shift.
- Toxic neutrophils may also be seenHematology: neutrophil Hematology: complete blood count (CBC).
Bacteriology
- Milk sample - culture and sensitivity Bacteriology.
- Escherichia coli, Staphylococcus spp or Streptococcus spp most commonly present.
Cytopathology
- Examination of milk sample shows neutrophils (with intracellular bacteria)/red blood cells.
Definitive diagnostic features
- History and clinical signs.
- Bacteriological culture and sensitivity results.
Differential Diagnosis
- Excessive milk production and lack of feeding leading to milk pooling in mammary glands (galactostasis).
- Mammary neoplasia Mammary gland: neoplasia.
- Mammary hyperplasia Mammary hyperplasia.
Treatment
Initial Symptomatic Treatment
- Start antibiotic therapy Therapeutics: antimicrobial drug with drugs considered safe for queen and kittens; eg broad spectrum beta-lactam antibiotics, eg amoxicillin Amoxicillin/clavulanic acid Clavulanate or cephalexin Cefalexin.
- Modify antibiotic therapy based on culture results and evaluation of milk pH.
- Remove kittens until therapy instigated.
- Suppress lactation by administration of cabergoline Cabergoline.
- Wean, feed artificially Milk replacers - this is controversial, some authors recommend nursing to empty gland.
- Most milk secretions from mastitis are alkaline, which favor the distribution of weakly acidic drugs such as ampicillin Ampicillin or cephalosporins.
- Distribution of weakly alkaline drugs such as trimethoprim sulfa Trimethoprim, erythromycin Erythromycin may be compromised if the pH is > 7.4
Standard Treatment
- Remove kittens - may need to wean/feed artificially until infection controlled.
- Suppress lactation by administration of cabergoline.
- Appropriate antibiotic therapy ideally according to milk culture and sensitivity results.
- Cold and hot packing of affected glands.
- Surgical drainage Drain: surgical wounds or mastectomy Mastectomy of abscesses/debridement of gangrenous areas as necessary.
- Antiseptic infusions into gangrenous or abscessed glands.
Monitoring
- Septicemic animals require IV fluids, antibiotics.
- Kittens weaned need good husbandry techniques.
Outcomes
Further Reading
Publications
Refereed papers
- Recent references from PubMed and VetMedResource.
- Wilson C R (2013) Feline gangrenous mastitis. Can Vet J 54 (3), 292-294 PubMed.
- Dernell W B, Kreeger J (1992) Peracute necrotizing mastitis as a cause of fatal septicemia and endotoxemia in a dog. Canine Pract 17 (6), 25-29 VetMedResource.