70 yo man referred for suspected subungual melanoma.HPI: The patient is a retired engineer with a one month history of subungual pigmentation. He suffers from Waldenstrom's macroglobulinemia and peripheral neuropathy. If he had injured his toe, he would not know.
O/E: The left middle toenail shows brown-blackish subungual pigmentation. It was difficult to appreciate if this was melanin or blood both clinically or dermoscopically. Hutshinson's sign is negative.
Dermoscopy before 3 mm punch biopsy
Diagnosis: Probably subungual hematoma. Need to r/o melanoma.
Procedure: Modification of Haneke Technique.
1. Patient soaks foot in warm water for 20 - 30 minutes
2. Carefully drive a 3 mm punch through the nail with care not to cut into the nail bed.
3. Lift off the cut disk of nail and observe the nail bed.
Dermoscopy after 3 mm punch biopsy and H2O2 to defect
In this case, what appeared to be dried blood was present. The area was cleaned with hydrogen peroxide and a normal appearing nail bed was see. There was no pigment noted. Dr. Hanecke's technique utilizes a Hemocult stick to test scraping from underside of nail, however, our strips were outdated and not reliable.
Note: Dr. Eckhart Haneke pioneered this technique but is not acknowledged in the literature. Here are his comments to this case: "Thank you very much for your email and the links, which I saw for the first time. Thank you also for giving me the credit.
You are completely right that we do not even need the hemoccult test strip for the correct diagnosis, but it is very convincing and impresses the patient. And of course, it is one more proof.
Also clinically, as this is no streaky lesion a melanoma is improbable - however, a very fast growing melanoma can appear like this.
When you apply hydrogen peroxide and the pigment disappears this is due to the hemodestructive action of H2O2 on erythrocytes: hemoglobin has a pseudocatalase action splitting H202 into H2O and O. That is why hydrogen peroxide is also a very good disinfective agent and I use it to cleanse my dermatosurgery field from blood."
Is the soaking the secret to soften the nail prior to using a punch. I was always a bit worried about the force I had to apply with a punch to get through a non soaked nail! The other useful technique is to use a dermatoscope but I agree this is much more convincing to a patient.
ReplyDeleteYes. Soaking is key. I think 20 minutes or more -- may depend on the age of the patient -- old people's nails are harder. Then just careful use of the punch. No anesthesia -- so you know if you are getting close. Once one does this one or two times one gets the feel. DJE P.S. I've done this three times and and each time I was surprised I didn't traumatize the nail bed.
ReplyDeleteThis is a niece posting about skin disease problem.
ReplyDeleteWishing you good luck.
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