Brief Answer:
Apply zinc oxide based cream

Detailed Answer:
Hi

Thanks for asking on this platform

I have seen the attached images. The most common cause of perianal rash in this age is diaper dermatitis. Other less common cause is transient lactose intolerance. Infetion is further less commoner cause.
To me it appears to be diaper dermatitis. There is no reducing substance in stool which is against the diagnosis of transient lactose intolerance. 4-6 pus cells in stool is also not a significant finding.
Applying Zinc oxide based creams like Rashfree helps in decreasing the inflammation and accelerates the healing of skin.Apply this cream at least 3-4 times a day. Keep the area dry and avoid rubbing while cleaning.
Just check if diaper absorption quality is good or not. The undersurface should not be wet after passing urine. Switching to a diaper of different brand with better absorptive capacity helps in such cases.
I hope with these measures the redness will subside.

Please let me know if you have any more questions.
Regards

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