Mercury poisoning affects multiple body systems, leading to variable clinical presentations. Mercury intoxication at low levels frequently presents with weakness, fatigue, weight loss, and abdominal pain. At higher levels of mercury intoxication, tremors and neurologic dysfunction are more prevalent.1 Dermatologic manifestations of mercury exposure vary and include pink disease (acrodynia), mercury exanthem, contact dermatitis, and cutaneous granulomas. Untreated mercury poisoning may result in severe complications, including renal tubular necrosis, pneumonitis, persistent neurologic dysfunction, and fatality in some cases.1,2
Pink disease is a rare disease that typically arises in infants and young children from chronic mercury exposure.3 We report a unique presentation of pink disease occurring in an 18-year-old woman following mercury exposure.
Case Report
An 18-year-old woman who was previously healthy presented to the hospital for evaluation of body aches and back pain. She reported a transient rash on the torso 2 weeks prior, but at the current presentation, only the distal upper and lower extremities were involved. A review of systems revealed myalgia, most severe in the lower back; muscle spasms; stiffness in the fingers; abdominal pain; constipation; paresthesia in the hands and feet; hyperhidrosis; and generalized weakness.
Vitals on admission revealed tachycardia (112 beats per minute). Physical examination revealed the patient was pale and fatigued; she appeared to be in pain, with observable facial grimacing and muscle spasms in the legs. She had poorly demarcated pink macules and papules scattered on the left palm (Figure 1), right forearm, right wrist, and dorsal aspects of the feet including the soles. A few pinpoint pustules were present on the left fifth digit.
Figure 1. Left palm with erythematous blanching macules coalescing into patches.
An extensive workup was initiated to rule out infectious, autoimmune, or toxic etiologies. Two 4-mm punch biopsies of the left palm were performed for hematoxylin and eosin staining and tissue culture. Findings on hematoxylin and eosin stain were nonspecific, showing acanthosis, orthokeratosis, and a mild interface and perivascular lymphocytic infiltrate (Figure 2); superficial bacterial colonization was present, but the tissue culture was negative.
Figure 2. A, A punch biopsy from acral skin demonstrated irregular acanthosis, orthokeratosis, and a mild perivascular lymphocytic infiltrate (H&E, original magnification ×20). B, Higher magnification showed few neutrophils present within a loosely lichenoid infiltrate, resembling lichenoid dermatitis (H&E, original magnification ×100).
Laboratory studies showed mild transaminitis, and stool was positive for Campylobacter antigen. Electromyography showed myokymia (fascicular muscle contractions). A heavy metal serum panel and urine screen were positive for elevated mercury levels, with a serum mercury level of 23 µg/L (reference range, 0.0–14.9 µg/L) and a urine mercury level of 76 µg/L (reference range, 0–19 µg/L).
Upon further questioning, it was discovered that the patient’s brother and neighbor found a glass bottle containing mercury in their house 10 days prior. They played with the mercury beads with their hands, throwing them around the room and spilling them around the house, which led to mercury exposure in multiple individuals, including our patient. Of note, her brother and neighbor also were hospitalized at the same time as our patient with similar symptoms.
A diagnosis of mercury poisoning was made along with a component of postinfectious reactive arthropathy due to Campylobacter. The myokymia and skin eruption were believed to be secondary to mercury poisoning. The patient was started on ciprofloxacin (750 mg twice daily), intravenous immunoglobulin for Campylobacter, a 2-week treatment regimen with the chelating agent succimer (500 mg twice daily) for mercury poisoning, and a 3-day regimen of pulse intravenous steroids (intravenous methylprednisolone 500 mg once daily) to reduce inflammation. Repeat mercury levels showed a downward trend, and the rash improved with time. All family members were advised to undergo testing for mercury exposure.