What could cause deformity in finger nail with crack and discoloration?

Q. I have deep crack in only one nail with yellow discoloration. Please help.

Answered by
Dr. Subhash Kashyap
and medically reviewed by Dr. Vinodhini. J
This is a premium question & answer published on Apr 22, 2020 and last reviewed on: Aug 11, 2023

Hi doctor,

I have a deformation on one of my fingernails with a deep crack and it is a bit yellow on a small part near the skin at the start of the nail. Please help.



Welcome to icliniq.com.

I went through the photo you sent. (attachment removed to protect patient identity). Most probably it is a fungal infection of the nail. But I want to confirm a few things before. How long it is there? Any history of trauma? Are you having high blood sugar or any other disease? Is it painful? Please answer these questions in the follow up because the short duration and more pain will be indicative of bacterial infection. For fungal of the nail, take capsule Itraconazole 200 mg twice daily after meals for seven days per month. (seven days then no dose for three weeks, then again seven days like this). Continue for three cycles then review.

The Probable causes:

The probable cause is fungal or bacterial or growth.

Investigations to be done:

Do GTT (glucose tolerance test) and KOH test.

Differential diagnosis:

The differential diagnosius is acute infection secondary to trauma and Beau's line due to internal disease.

Probable diagnosis:

The probable diagnosis is onychomycosis.

Treatment plan:

Take antifungal for one week per month for a minimum of three months.

Preventive measures:

Avoid wet work. Keep hand dry.

Thank you doctor,

I noticed it around a month ago. No trauma or I did not notice it. No history of high blood sugar or other disease and it is not painful.



Welcome back to icliniq.com.

That's good. It is a fungal infection of the nail bed only. Follow the treatment given and it will slowly grow out.

Was this answer helpful?


Same symptoms doesn’t mean you have the same problem. Consult a doctor now!

Related Questions:
Is fungal infection the main cause for losing skin on my penis?

.. common cause will be a fungal infection, and the treatment will be with Canesten cream (Clotrimazole) to apply twice daily for a week. But since the lady is also symptomatic, it is better to go for STD (sexually transmitted disease) screening for both   Read full

Nails appear to be unfixed in the skin. Can this issue be treated?

.. the clinical picture (attachment removed to protect patient identity). It looks like twenty nail dystrophy. This is a clinical diagnosis. Some cases are genetic and some are acquired. The cause for the nail dystrophy is not very well known.   Read full

I have a black spot on my toenail. Could this be a blood clot?

.. Do you have any minor trauma? Excess contact with water? Are you a diabetic or any chronic illness? Do you have any drug history? Differential diagnosis are fungal infection (onychomycosis) and subungual melanosis.   Read full

Also Read Answers From:

ideaComprehensive Medical Second Opinion.Submit your Case

Also Read

PCOS and Liver Problems
The hormonal imbalances in polycystic ovary syndrome could cause liver diseases. Read the article to know the relationship between these medical conditions.  Read more»
Inferior Alveolar Nerve Lateralization Technique
The inferior alveolar nerve lateralization technique is a surgical lateralization technique to reposition the nerve. Read the article to know more about this.  Read more»
COVID-19 and Ebola: Similarities and Differences
This article gives a comparison and broader overview of the outbreak of the two deadliest diseases that showed a greater incidence over the last two decades.  Read more»

Ask your health query to a doctor online?

Ask a Dermatologist Now

* guaranteed answer within 4 hours.

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.