Acupuncture point injection (API), emerged in China during the 1950s, has been widely accepted and used in various diseases in Oriental medicine12. API is a modified acupuncture technique, injecting liquid agent like herbal extracts into acupoints through acupuncture needles, mainly to relieve pain12. It is believed to have a more sustained effect than conventional acupuncture by playing a synergistic effect with acupoint stimulation, but has limited clinical evidence2.

Acupuncture associated dermatoses commonly manifest as infection and hypersensitivity reactions1, but its pathophysiology is still unclear. Cholesterol granuloma is a foreign body reaction to crystallized cholesterol, induced by breakdown of blood components after trauma34. It shows male predominance and usually found in the frontal bones, zygomatic, and petrous temporal bones with a history of trauma34. We present a rare case of multiple cholesterol granulomas arising from the site of API with herbal ingredient. We received the patient's consent form about publishing all photographic materials.

A 55-year-old Korean female presented with a fifteen-year history of multiple brownish subcutaneous firm nodules on the trunk. She had been treated with API by oriental medical doctor in order to relieve unexplained generalized pain. Despite of a number of attempts of API with unidentified herbal ingredient, the symptom did not improve. Thereafter, small brownish firm nodules appeared on the trunk insidiously over the years, which were confined only to sites of injections and gradually increasing in numbers and sizes up to 5 to 7 mm in diameter (Fig. 1A~D). There were no laboratory findings suggestive of severe systemic adverse reactions, while the patient had significant cosmetic disfigurement. The excisional biopsy was performed at the papular lesion on the abdomen. Histologic findings revealed a large number of spindle shaped cholesterol cleft surrounded by multi-nucleated giant cells, which were supportive for cholesterol granulomas (Fig. 1E~G). Dozens of subcutaneous nodules were removed at the patient's request. She is being followed up at regular intervals without complications so far. In this case of our patient, multiple cholesterol granulomas were developed from acupuncture sites after API. Although the pathophysiology of cholesterol granuloma is not fully understood, a traumatic or inflammatory event can lead to tissue hemorrhage, followed by formation of crystalline complexes to cholesterol from the destroyed cell membranes4. As a result, a slow-growing mass can be developed4. Xanthoma, cutaneous cholesterol emolization, necrobiosis lipoidica diabeticorum, and necrobiotic xanthogranuloma, which can show cholesterol cleft on pathology, could be considered as differential diagnosis5. Acupuncture is a kind of traumatic event, but cholesterol granuloma does not necessarily occur after acupuncture in general. Since the lesions occurred in most sites of the API, we thought that herbal ingredient could have contributed to the development of cholesterol granuloma or could be a direct cause itself. There have been only a few reports about foreign body granulomas occurred after API with herbal ingredient1, but no report of cholesterol granuloma so far. Given the fact that acupuncture is widely used empirically in the absence of clinical consensus, we strongly suggest that the clinician should be concerned about the various skin diseases that may occur after acupuncture.