Risk of squamous cell carcinoma of the lip and cutaneous melanoma in older Australians using hydrochlorothiazide: A population-based case-control study

Recent European and US studies reported increased risks of skin cancers associated with hydrochlorothiazide (HCTZ) treatment. Our study aimed to determine the risk of lip cancer and malignant melanoma among Australians prescribed HCTZ. We conducted a case-control study nested within a population of veterans residing in New South Wales in 2004-2015, using Australian Department of Veterans' Affairs data linked with cancer registrations, hospitalisation and prescription dispensings. Among DVA healthcare card holders 65 years and older, we identified incident cases of squamous cell carcinoma of the lip and of cutaneous melanoma, each matched with up to 20 controls through risk-set sampling. We estimated odds ratios (ORs) associating HCTZ use with each cancer using conditional logistic regression, adjusting for predefined confounders. For lip cancer (45 cases), ever-use of HCTZ yielded an OR of 2.6 (95% CI: 1.4-5.0) and high HCTZ use (≥25 000 mg) an OR of 4.7 (95% CI: 1.6-13.7). For cutaneous melanoma (659 cases), ever-use of HCTZ resulted in an OR of 1.2 (95% CI 1.0-1.5) and high HCTZ use in an OR of 1.2 (95% CI: 0.8-1.8). Our findings align with risk estimates from previous studies and provide further evidence that HCTZ's photosensitising properties may promote carcinogenesis in sun-exposed tissues.

Sparfloxacin-induced photo-onycholysis and photosensitivity characteristically sparing lepromatous skin lesions: an interesting observation

Sparfloxacin is an antibiotic in the quinolone group of antibacterial agents, which often induce photosensitive skin reactions, more often phototoxic reactions than photoallergic ones, and sometimes associated photo-onycholysis. We present a case of phototoxic dermatitis with photo-onycholysis in a 38-year-old man probably induced by sparfloxacin, which was prescribed to him along with rifampicin and clofazimine because he was suffering from borderline lepromatous leprosy. He developed exaggerated sunburn-like eruptions mainly on sun-exposed sites along with painful onycholysis of the fingernails. Interestingly, the hypopigmented patches of leprosy were spared, which is a very rare phenomenon. Withdrawal of sparfloxacin along with administration of systemic steroids and other supportive measures helped heal the skin eruptions with hyperpigmentation, but the photo-onycholysis was slow to resolve.

Low risk of postinflammatory hyperpigmentation in skin types 4 and 5 after treatment with fractional CO2 laser device

BACKGROUND/OBJECTIVE

Hyperpigmentation occurs in more than 37% of dark-skinned subjects treated with a fully ablative CO2 laser device. This study assessed the risk of postinflammatory hyperpigmentation (PIH) in subjects with skin types 4 and 5 treated once with a specific protocol of treatment using a fractional CO2 laser.

METHODS

Seven subjects with photodamaged skin received a single facial treatment using a fractional CO2 laser. Anesthesia was limited to a lidocaine and prilocaine cream for 1 hour before the single-pass treatment. Subjects were evaluated for improvement and PIH on alternate days for 14 days, and at 1 month, 3 months, and 6 months posttreatment.

RESULTS

All subjects achieved improvement in their specific skin conditions and in skin texture. Postinflammatory hyperpigmentation was not observed in any subject. Four subjects experienced no pain during treatment, while 3 reported mild pain. Recovery was associated with minimal pain and itching.

CONCLUSION

In dark-skinned subjects, fractional CO2 laser treatment and topical anesthesia subjectively improves common skin conditions without PIH.

Cheilitis: analysis of 75 cases referred to a contact dermatitis clinic

BACKGROUND

Cheilitis is a common problem, the cause of which is often obscure.

OBJECTIVE

Data on 75 cases of recalcitrant cheilitis were analyzed. These had been referred to a tertiary care center.

METHODS

Each of the 75 patients had undergone a detailed history, physical examination, and patch tests.

RESULTS

Of the patients, 53 were female (67%), and the age range was 9 to 79 years. Of the cases, 36% included irritant contact dermatitis (ICD), 25% included allergic contact dermatitis (ACD), 19% were attributed to atopic eczema, and in 9% the dermatitis was of unknown cause. Nine percent were noneczematous. The materials causing ACD were medicaments applied to the lips, lipstick ingredients, sunscreen agents, toothpaste ingredients, colophony in dental floss and toothpicks, nail varnish, cosmetics, and nickel in the mouthpiece of a flute.

CONCLUSION

The most common cause of cheilitis was irritation, frequently caused by liplicking. About one quarter was caused by ACD. Medicaments, lipsticks, sunscreens, and toothpaste were the most common allergens. Atopic eczema is a commonly overlooked cause of cheilitis. However, there is a troublesome group of patients, 9% in this series, who are often severely affected, but the cause of their cheilitis remains obscure.