Brief Answer:
Infection of small anal glands

Detailed Answer:
Hi,
Thanks for choosing health care magic for your query!

An anal abscess is a painful condition in which a collection of pus develops near the anus. Most anal abscesses are a result of infection from small anal glands. The most common type of abscess is a perianal abscess. This often appears as a painful boil-like swelling near the anus.
Risk factor anal abscess is infection of small glands which are located near the anus,Infection of these glands causes formation of pus around this area,A untreated infection causes infection to spread from one gland to another causing multiple abseccse,Crohn's disease or ulcerative colitis and diabetes are among other common causes.
As said by you;You have taken 7 rounds of antibiotic.Regular use of antibiotics have causes depletion of you gut flora.Most commonly antibiotics cause for the depletion of Gastrointestinal flora due to use of antibiotics.Gut flora is the complex community of microorganisms that live in the digestive tracts of humans,The intestinal microflora is a complex ecosystem containing over 400 bacterial species. Anaerobes outnumber facultative anaerobes. The flora is sparse in the stomach and upper intestine, but luxuriant in the lower bowel.Toxins released by bacteria destroys this flora of gut and lead to various problems with digestive system including nausea inability to digest food,Loss of appetite,Malaise.
I would recommend you to take a course of probiotics so that the destroyed flora can be replenished ,once the intestinal flora will become normal,Gut mobility and digestion will improve and things will settle down.
Proton pump inhibitor like pantoprazole can also be taken for few days along with probiotic.Please discuss the options with your gastroenterologist.

Now as per your questions-
Poisoning is very less likely to be associated with multiple anal abscesses,Its most commonly caused by infection.Recurrent infection is the most likely cause in your case.

Thanks

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Brief Answer:
Usually no but if bacteria reaches blood it can cause septicemia.

Detailed Answer:
Hi again,
Usually it can not cause death but if the bacteria some how reaches the blood then this is called septicemia,and may even cause the patient to land up in septicemic shock which can be fatal also.Sepsis has mortality rate of over 90%.Hence a good antibiotic coverage should always be given to patient and any abscess should be drained out by surgical intervention.

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