Also Known As: Balanitis, swelling of the head of the penis, swelling of the glans of the penis
Balanitis is inflammation of the glans penis. When the foreskin (or prepuce) is also affected, it is termed balanoposthitis. Balanitis on boys still in diapers must be distinguished from the normal redness seen in boys caused by ammoniacal dermatitis.
Inflammation has many possible causes, including irritation by environmental substances, physical trauma, and infection by a wide variety of pathogens, including bacteria, virus, sexually transmitted diseases, or fungus—each of which require a particular treatment.
O'Farrell et al. report that failure to wash the whole penis, including retraction of the foreskin in uncircumcised men, is more common among balanitis sufferers. Birley et al., however, found that excessive genital washing with soap may be a strong contributing factor to balanitis.  Diabetes can make balanitis more likely, especially if the blood sugar is poorly controlled.
In a study by Fergusson et al., penile inflammation was reported in 7.6 cases per 100 boys at risk in circumcised boys, and 14.4 cases per 100 boys at risk among uncircumcised boys. Herzog and Alvarez reported that, in their study, "[both] balanitis (6% vs 3%) and irritation (4% vs 1%) were more frequent among the uncircumcised children, but the difference was not statistically significant." Van Howe found that circumcised boys need to be as or more closely monitored for balanitis than uncircumcised boys. In Wilson's study, all 22 cases of balanitis were among uncircumcised men. However, the number of cases was "too small to be of significance". In a retrospective study including 28 cases of monilial balanitis, Taylor and Rodin found this condition to be more common among uncircumcised men. In a study assessing the effects of a war environment on sexual health, Hart reported that balanitis was "almost entirely confined to the uncircumcised". In a cross-sectional study of 398 patients, Fakjian et al. reported that balanitis was diagnosed in 12.5% of uncircumcised men and 2.3% of circumcised men. In a study of 225 men, O'Farrell et al. found that circumcised men were less likely to be diagnosed with balanitis than uncircumcised men. In Mallon's study of 357 patients with genital skin diseases and 305 controls, most cases of inflammatory penile dermatoses (and all patients with nonspecific balanoposthitis) were uncircumcised.