It is accepted medical knowledge that people with diabetes have an increased susceptibility to infection. A recent review in December 16, 1999 issue of the New England Journal of Medicine shows the most common infections associated with diabetes; and in which instances the jury is still out. Many specific infections appear more frequently in diabetic patients, and others occur almost exclusively in them. Diabetes has been implicated as a risk factor for salmonella, staph and candida infections. There is evidence that more closely controlled glycemic levels will improve immune function. Diabetic patients do experience some alteration of their immune function, such as depressed leucocyte levels or a reduced ability by the body to combat bacteria (phagocytosis). But it would be best to look at some of these conditions individually, rather than draw the more general assumption.
Respiratory Tract Infections
Infections caused by two micro-organisms (staphyloccus aureus and mycobacterium tuberculosis) happens more often in patients with diabetes. Although diabetic patients appear to have an increased mortality rate in cases of pneumococcal pneumonia, they have a normal response to vaccination. It is recommended that patients with diabetes be vaccinated for both influenza and pneumococcus.
Urinary Tract Infections
Studies show that hospitalized diabetic women are more prone to urinary tract infections; but this may in fact be due to the increased use of urinary tract catheters. Diabetes is a predisposing factor for those urinary tract infections caused by fungi (particularly candida). Preferred treatment includes removal of any catheter, and the administration of an oral dose of flucanazole.
Foot infections are the most common of soft-tissue infections in people with diabetes. It usually requires a multidisciplinary approach to treat successfully.
Other than foot infections, necrotizing fascitis (also known as the flesh-eating disease) is a serious soft-tissue infection that diabetic patients can be susceptible to, with the mortality rate approaching 40%. Necrotizing fascitis is most common in the arms, legs and the abdominal wall. Fully 90% of these cases are caused by a bacilli such as E. coli; which are considered part of a class of polymicrobial infections.
In dealing with any infections of this sort, emergency evaluation and treatment are imperative; usually in the form of broad spectrum intravenous antibiotics. A combination of penicillin and clindamycin is usually administered.
The following infections occur mainly in people with diabetes:
- A particularly nasty infection, caused by an organism called pseudomonas aeruginosa, can invade the outer ear and result in a potentially life-threatening infection. The infection can be misdiagnosed, since it is not that common. Once diagnosed, treatment includes topical drops and a systemic antibiotic for four to six weeks.
- Another infection involves a parasitic fungi which invades the nasal passage, referred to as rhinocerebral mucormycosis. About half of all these cases occur in diabetic patients.
- An infection of the gallbladder which is often associated with diabetes is emphysematous cholecystitis. Although uncommon, about 35% of the cases occur in diabetes patients.
- An infection of the kidneys, emphysematous pyelonephritis, occurs almost exclusively in diabetic patients (over 90% of cases). The majority of these cases are caused by E.coli. Hydration, intravenous antibiotics and aggressive control of hyperglycemia are important in initial treatment; but most cases will require some surgery.
According to Joseph Prendergast, MD, physicians need to be more familiar with the types of infections that people with diabetes are most susceptible to. “[Having] a list of the microorganisms that cause problems is important,” he says. “Group B strep causes 27% of all infections [in people with diabetes] and klebsiella may account for 30_60% of all infections. Therefore, treatment can take these two [kinds of infections] as the first consideration before any culture results have returned.”