Urinary tract infection (UTI) is the collective term used to describe infections involving any part of the urinary tract, which includes the kidneys, ureters, bladder and urethra. Infections of the bladder (cystitis) and urethra (urethritis) are known as lower UTIs and infections of the kidneys (pyelonephritis) or ureters are classed as upper UTIs.
The use of D-Mannose in the prevention of recurrent UTIs has shown benefit, and with the added potential to offer a valuable alternative to antibiotics.
By virtue of their patient access, community pharmacists can provide front-line health education and screenings to female patients. Diagnosis of UTI is based primarily on signs and symptoms.
The incidence of UTIs in adult males under age 50 years is low. Up to 40% of women develop a UTI at some point in their life, compared to 12% in men. In men, cystitis is often associated with infection and inflammation of the prostate gland (prostatitis). Anatomically, the female urethra is shorter and located closer to the anus than in males, which makes it easier for bacteria to reach the female urethra and bladder. Adult women are 30 times more likely than men to develop a UTI, with almost half of them experiencing at least one episode during their lifetime and one-in-three women experiencing their first episode by the age of 24 years. UTIs are most commonly seen in sexually-active young women.
If patients present with both dysuria and frequency, the probability of a UTI is greater than 90%, making the diagnosis of UTI (without the need for urinalysis) almost certain. The results of several studies have revealed that antibiotics may promote treatment resistance by causing alterations in the intestinal flora. Symptomatic treatments available over the counter (OTC) from community pharmacies include alkalinising agents, cranberry products, and analgesia.
UTIs can be classified as ‘uncomplicated’ (sometimes referred to as a ‘simple’ UTI) or ‘complicated.’ Uncomplicated infections present most frequently in women without any structural or functional abnormality of the urinary tract, any history of renal disease, or other comorbidity (e.g. immunocompromised patients or those with diabetes), which may contribute to more serious outcomes. Complicated UTIs are associated with a condition or underlying disease that interferes with the patient’s immune mechanisms and increases the risk of acquiring infection.
Recurrent UTIs, defined as at least two UTIs in 6 months or three UTIs in 1 year, are a significant burden for the patient and result in high costs to the health system. The most commonly prescribed regimens are trimethoprimsulfamethoxazole (or trimethoprim alone), nitrofurantoin, cephalexin and the fluoroquinolones at a quarter of the usual daily dose for 6 months.
The downsides of long-term antibiotic prophylaxis are possible adverse reactions (although rare), costs and increasing bacterial resistance to antibiotics; therefore, alternative prophylactic agents, such as cranberry juice and probiotics have been extensively studied. One such agent is D-mannose, which is normally present in human metabolism and has an important role, especially in the glycosylation of certain proteins. The supposed mechanism of action is inhibition of bacterial adherence to urothelial cells. In vitro experiments have shown that D-mannose binds and blocks FimH adhesin, which is positioned at the tip of the type 1 fimbria of enteric bacteria.
D-mannose powder has been available for some time for the treatment of UTIs in horses, cats and dogs. Its efficiency has not been validated in larger studies but it has been shown that in vitro D-mannose applied locally reduces the adherence of Escherichia coli, Pseudomonas aeruginosa and Streptococcus zooepidemicus (important causes of sterility in mares) to endometrial epithelial cells in mares.
D-mannose is also widely available and used for UTI prevention in humans as a food supplement, but clinical studies on the topic are lacking.
One study carried out by Silvio Altarac and Dino Pape of the Department of Surgery and Urology, Zabok General Hospital and the Department of Paediatric Surgery and Urology, Clinical Hospital Centre Zagreb looked at the use of d-mannose in prophylaxis of recurrent urinary tract infections (UTIs) in women. The results of this study suggest that D-mannose can be an effective prophylactic agent in a selected population.
The study authors state, “The latest Cochrane Database review concluded that cranberry products cannot currently be recommended for the prevention of recurrent UTIs, although there are many good-quality studies that clearly showed its efficacy in selected patients.
“A possible cause of such a finding and contrasting results among clinical studies is that in many of them various cranberry products (powder, juice, capsules) without clearly defined potency, dosing and active ingredient contents have been used, which is a known problem with natural food supplements. To avoid such issues with D-mannose, pharmacokinetic studies to determine the exact dosage and optimum regimen for D-mannose should be undertaken in further research. We believe that D-mannose may be a useful agent for the prevention of recurrent UTIs but further clinical trials will be necessary.”