Contact dermatitis after ultrasonography and electrocardiography

[A Case of Contact Dermatitis Due to Ultrasonography Gel]

A 60-year-old female had a subcutaneous mass in the B region of the left breast. A needle aspiration cytologic examination revealed class IV, and she was referred to our surgical department for examination and treatment. She underwent an ultrasound echography on bilateral the mammary glands and axillary lymph nodes. Erythematous papules and plaques were revealed on her left breast, left axilla, and in the center of the chest area. The patient was referred to our dermatology department for evaluation of her skin eruption. Histopathological examination revealed the infiltration of lymphocytes and eosinophils in the perivascular of the upper dermis with spongiosis and liquid degeneration in the epidermis. A patch testing showed a positive reaction to ultrasonography gel. Based on the clinical course and examinations, we diagnosed her skin eruption as contact dermatitis due to ultrasonography gel. Her skin eruption improved rapidly by topical application of betamethasone butyrate propionate ointment. Recurrence of her skin eruption could be avoided by the removal of the gel after the ultrasonography examination. Our case report demonstrated to us that contact dermatitis could be prevented by promptly wiping off the ultrasonography gel from the skin after the examination.

Absence of neurotoxicity with perineural injection of ultrasound gels: assessment using an animal model

Background

Ultrasound gels may contain propylene glycol and glycerol, which are neurotoxic in high concentrations. If the needle passes through gel during regional anesthesia, gel may be injected near the nerve. It is unknown if this practice poses a risk for neurotoxicity. Using an animal model, we assessed the histological changes of perineural propylene glycol on nerves. We then assessed three commonly used sterile gels for evidence of neurotoxicity.

Methods

Micro-ultrasound guided perineural sciatic nerve injections were performed in mice. Propylene glycol (PG) 2.5%, 10%, 35%, 70% (v/v) or saline was injected. Nerves were assessed after three days for evidence of neurotoxicity. Aquasonic® 100 Ultrasound Gel, K-Y® Lubricating Jelly, and PDI® Lubricating Jelly were also studied against saline controls.

Results

Confluent areas of axonal degeneration and intraneural inflammation occurred in 5 of 9 specimens injected with 70% PG. At 35%, 2 of 8 specimens showed patchy changes not present at lower concentrations. No degeneration occurred with Aquasonic® 100 or PDI® Lubricating Jelly. In the K-Y® group, one gel and one saline specimen demonstrated confluent degenerative changes.

Conclusions

Similar to glycerol, 70% PG may cause confluent areas of axon and myelin degeneration with associated intraneural inflammation. The concentration of PG present in ultrasound gels is unlikely to cause neurotoxicity. Aquasonic® 100 and PDI® Lubricating Jelly did not cause neurotoxicity. The results for K-Y® Lubricating Jelly are inconclusive. There is no evidence that passing the needle through the studied gels during regional anesthesia procedures is harmful.

Propylene glycol-induced proximal renal tubular cell injury

Propylene glycol is a solvent that is used in many oral, injectable, and topical medications. Although uncommon, acute renal failure has been attributed to propylene glycol. The mechanism of propylene glycol-mediated renal injury is unknown. We report a case of acute renal failure in a 16-year-old boy given large doses of pentobarbital and phenobarbital, both of which are solubilized with propylene glycol. A renal biopsy showed proximal renal tubular cell swelling and vacuole formation. The data from this case suggest that the reversible acute renal failure caused by propylene glycol is attributable to proximal renal tubular cell injury.

Propylene glycol dermatitis

Propylene glycol is a commonly used vehicle for topical preparations. Although it is well suited for this purpose, it is capable of producing both primary irritant skin reactions and allergic sensitization. The literature on propylene glycol is reviewed, with particular attention to the nature of these adverse cutaneous effects. Guidelines for patients sensitive to propylene glycol are discussed.