Brief Answer:
Probably obesity related Acanthosis Nigricans, needs evaluation.

Detailed Answer:
Hello Mr XXXXXXX

Thank you for posting your query here.

I have read your query and have seen the attached pictures.

There is some minor hyperpigmentation (skin darkening), and could well mean that the darkening has just started and it can get worse with age.

There are multiple causes for such hyperpigmentation, I will list a few, so that you get an idea of what we are dealing with and also understand the reasons why I will suggest to you to get her evaluated.

1. Type - I Acanthosis Nigricans - Heriditary in nature, presents in childhood.
2. Type - II Acanthosis Nigricans - Caused by endocrine abnormalities like hypothyroidism, Cushing's disease, pituitary adenoma, acromegaly, insulin resistance, Prader-Willi syndrome etc.
3. Type - III - obesity and pseudoacanthosis nigricans.
4. Type IV - drug-related - Some hormones/setroid drugs can cause similar condition
5. Type V - malignancy (rare)- Occurs as a paraneoplastic syndrome, generally gastrointestinal adenocarcinomas, carcinomas of the lungs etc can also cause some hyperpigmentation.

So, since some of the causes can be serious, I suggest you to kindly get her evaluated by a pediatrician and get it investigated properly to come to a possible diagnosis.

Though from the pictures it appears to be Obesity related in my opinion, it needs further testing.

I hope this answers your query.

Feel free to write back to me if you have any more questions.

Best regards

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Brief Answer:
Consult an endocrinologist and skin specialist, new pediatrician.

Detailed Answer:
Hello again Mr XXXXXXX

I can understand your dilemma.

I would suggest you to consult an endocrinologist, skin specialist and a different pediatrician.

All these doctors must work as one team and carefully arrive at a proper diagnosis.

Interdisciplinary collaboration is essential in such cases.

I hope you get my point.

Best.

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