In September, 2012, a 37-year-old man attended our clinic a month after noticing the appearance of small erythematous papules underlying a 12-year-old tattoo on his right leg. He also complained of progressive muscle ache in both his legs. 2 weeks before coming to the clinic, he started having pain and swelling of both ankles, and also noticed fever, fatigue, and night sweats. Physical examination showed swelling of both ankles and erythema over the Achilles tendon; the area was very tender to palpation and the patient had limited range of motion. Over the lateral aspect of the right leg there was an ovoid blue to grey tattoo; within the areas of tattoo ink were scattered well-demarcated pink papules and plaques with overlying white scale (fi gure). Laboratory investigations showed normochromic, normo cytic anemia, erythrocyte sedimentation rate of 105 mm/h, raised 1,25-dihydroxivitamin D, normal calcium and angiotensin converting enzyme concentrations, and HIV serology was not reactive. Chest radiography showed bilateral linear opacities and hilar adenopathies. Tuberculin skin test was not done because of previously treated latent tuberculosis infection 10 years ago. Reactive arthritis was suspected but the patient did not report multiple sexual partners or urinary symptoms. Urinary DNA analysis for chlamydia and gonococcus was negative. Rheumatological blood tests were normal, and blood cultures were negative. Chest CT scan was done and showed hilar and subcarinal adenopathies. A punch biopsy of the lesion over the tattoo was done: it showed non-caseating granulomas compatible with sarcoidosis (fi gure). The diff erent stains in the biopsy specimen were negative for infectious agents. Ophthalmological assessment was unremarkable. The patient was started on oral prednisone and showed striking improvement within a few days. He was discharged, and at last follow-up in January, 2013, he was symptom free. Prednisone had been tapered off at that time. Skin involvement in sarcoidosis occurs in 20–35% of cases, usually in early stages of the disease, providing a valuable opportunity for timely diagnosis. The fi rst report that related tattoos to systemic sarcoidosis was published in 1955, and 32 reports in total were published before 2012. Sarcoid lesions usually occur in the red (cinnabar), black (ferric oxide), and blue-black areas of tattoos. The age of the tattoo before sarcoidal manifestations is widely variable and ranges from months to decades. Chronic low-grade exposure of the immune system to an antigen substance in the foreign material might ultimately lead to systematised granulo matous hypersensitivity. The association of new-onset pronounced ankle arthritis and bilateral hilar lymphadenopathy without erythema nodosum, especially in men, has been suggested as a variant of Lofgren’s syndrome, and this pattern of ill ness has an excellent prognosis. Tattoo sarcoidosis, as described in our patient, could be the fi rst manifestation of sarcoidosis. The importance of skin biopsy during the initial assessment should be remem bered, and this clinical presentation should alert the clinician to an early diagnosis.