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My roommate has had an ongoing problem for years now. On certain areas of her skin, particularly around the neck, armpits, and inner thighs, her skin has darkened, almost to blackness (she is white, 24 years old) and the skin is rough and very creased. She is very embarassed about it and is reluctant to seek help. This problem seems to have started about 5 years ago when she started putting on a lot of weight. What is this and should she be concerned?

2nd December 2024

It is unfortunate that your roommate has suffered for so long with this problem. Try to reassure her that she does not need to feel embarrassed or worried about her problem and that a visit to her doctor can almost certainly result in an improvement. The regions of skin that you mention may be affected by an infection that prefers the slightly damper conditions in those regions, and it is possible that the darkening is due to prolonged scratching and rubbing because of itching and irritation. Another possibility is that there may be an underlying metabolic disorder, but either way the doctor will most likely be able to bring about a significant improvement.

My husband has had a rash off and on since April of 2024. In April, he had surgery on his finger for a high pressure injection injury from an airless paint spray rig. He injected lacquer thinner and oil based paint into his finger, thankfully they got it all out…during his 3rd surgery a skin graft, he had an allergic reaction to a medication…. I cannot remember the name of the medication and the plastic surgeon does not feel the need to let us know the name… Anyway, off and on since those surgeries, he has had a hive like rash that has been treated with shots of steroids, steroid pills, and topical steroids. It goes away for a few days then pops back up… We have seen 3 different general practitioners, an internist/allergist, and a dermatologist… they all tell us the same thing. You have bad skin… he has tried herbal remedies… and frankly we are at our wits end with this rash… Maybe you can tell me about another medication that might help my husband, because, frankly, he is driving me nuts and I know this rash is driving him nuts.

13th March 2025

Even though it is more than a year since your husbands injury, it is possible that his immune system is still sensitised to the paint/thinner mixture that was injected into his finger. There may be small residues of these substances in his tissues that are still being dealt with by inflammatory tissue reactions. If this is the case, the skin rash should become less of a problem as time goes by. You did not mention whether or not he has returned to the same work since the accident. If he is sensitised to those substances, then any additional exposure via skin contact or through breathing contaminated air could aggravate the problem. The ability of various steroid-based treatments to reduce the rash for a while does seem to indicate that the immune system is involved. It may help to remember that although the symptoms are distressing for you both, they are probably a consequence of an ongoing protective mechanism.

High-pressure injection injuries to the hand are potentially very disabling, so it is reassuring that your husband received comprehensive and effective treatment. Airless paint sprayers, high pressure grease guns, and fuel injection apparatus deliver materials at pressures ranging from 600-12,000 psi, and at these pressures substances penetrate through a small skin wound with great kinetic energy and spread widely within the tissues. Here they compress blood vessels, cause severe chemical irritation, and introduce bacteria (Mrvos, Dean, and Krenzelok, 2012; Ebelin, 2019). The index finger on the non-dominant hand is most commonly involved (Jebson et al, 2018). Injuries to digits are potentially more disabling than those to the palm of the hand (Hayes and Pan, 1982).

Paint is very toxic and causes considerable tissue inflammation (Lewis 1985; Zook and Kinkead, 1979). The potential hazards are death of tissues aggravated by infection, with the result that amputation becomes necessary in up to half the cases (Lewis et al, 2023; Schnall and Mirzayan, 2024). At first sight the injury may look relatively benign, but this appearance is deceptive and there should be no delay in surgery to reduce pressure within the tissues and remove the contaminating fluid (Karlbauer and Gasperschitz, 2012; Neal and Burke, 2016; Flotre, 2017; Jebson et al, 2018). An open wound technique with delayed closure has been found to be beneficial (Pinto et al, 2018). Antibiotics are given routinely after such an injury to reduce the risk of infection, and although steroids are commonly given to limit the severity of inflammatory response (Phelps, Hastings, and Boswick, 1977; Edlich, Rodeheaver, and Edgerton, 1978), there is still discussion about whether this is necessary (Sirio, Smith, and Graham, 2014).