Question: What is the best diagnosis code to report for bladder erythema? I’m deliberating between N32.9 and N32.89. Missouri Subscriber Answer: The most appropriate diagnosis for bladder erythema is N32.89 (Other specified disorders of bladder). Erythema is a superficial reddening, usually in patches. The condition may be caused by an injury or some type of irritation that results in dilatation of the blood capillaries. From a urology perspective, bladder erythema could be a sign of cancer, ie, carcinoma in situ, D09.0 (Carcinoma in situ of bladder), that merits further investigation.