PUPPY DIARRHEA: BACTERIAL INFECTIONS
Bacterial enteritis by far most common cause of diarrhea in young puppies followed by parasitic enteritis. Known bacteria that cause enteritis includes Salmonella, Campylobacter jejuni (C, jejuni), Clostridium perfringens, Enteropathic E.coli and Yersinia pestis.
Salmonella and C.jejuni are isolated from the majority of cases of bacterial enteritis. Salmonella, C.jejuni and Clostridium perfringens can invade intestinal mucosa and cause dysentery ( diarrhea with blood ) and even septicemia.
Hemorrhagic gastroenteritis (diarrhea with blood)
In certain stress conditions like hospitalization and sudden diet change Clostridium perfringens produce enterotoxins that can disrupt intestinal mucosa leading to hemorrhages. Hemorrhagic gastroenteritis is accompanied by marked hemoconcentration.
SIBO (Small intestinal bacterial overgrowth) is a peculiar condition where the number of bacterial microflora increases causing acute and chronic diarrhea in dogs. However recently it is advised that qualitative change in bacterial microflora is more important than the quantitative change in causing enteritis. Now term ARD (antibiotic-responsive diarrhea) is used for diarrhea that responds to antibiotics. This may involve SIBO and pathogenic bacterial infections.
A stool test is most important for all diarrhea cases. Fecal culture should be done if fecal neutrophils are identified in basic stool test. Culture test can isolate the bacterial cause. A simple CBC test may be suggestive of nature of infection and help in therapy. Liver and Kidney function test are important in choosing appropriate therapy and drugs.
The aim of therapy should be:
- To replenish lost fluids due to diarrhea.
- To restore electrolytes balance.
- To maintain normal blood pressure.
- Treat or prevent septicemia and bacteremia.
- Stop vomiting.
Fluid therapy is most important in survival rates and recovery time in diarrhea cases in puppies. Fluids like Ringer Lactate with Dextrose can replenish lost fluid and help in hypoglycemia condition. Colloids can also be used in to restore normal blood pressure.
Adding potassium to fluid therapy may help in restoring normal potassium level in hypokalemia cases.
Antiemetics like metoclopramide, ondansetron are effective in controlling vomiting. Atropine sulfate can also be used but not often recommended.
Antibiotics may not be required in most cases of puppy diarrhea. But in severe cases, especially where gastrointestinal mucosa is disrupted antibiotics should be used to prevent or treat bacteremia or septicemia. Mostly broad-spectrum antibiotics are used like ampicillin. First generation cephalosporins are often used. Fluoroquinolones are sometimes added with Cephalosporins. Erythromycin is the drug of choice for Clostridium perfringens infection.