Tattoo-associated granulomatous reaction: This is the most likely diagnosis given the presence of skin granulomas exclusively on tattooed areas, particularly with black and pink ink. The reaction is thought to be caused by an immune response to the tattoo ink, leading to granuloma formation.

Sarcoidosis: Although the lung biopsy did not show granulomas, sarcoidosis can present with skin granulomas and mildly enlarged lymph nodes. The normal lung function test and EKG reduce the likelihood, but it remains a possible diagnosis.
Contact dermatitis: An allergic reaction to the tattoo ink could cause a granulomatous response, especially if the patient has a history of allergies or sensitivities.
Foreign body reaction: The introduction of foreign substances (tattoo ink) into the skin can trigger a granulomatous response, similar to a foreign body reaction.

Lymphoma: Although the biopsy did not show granulomas, it is essential to consider lymphoma, especially with mildly enlarged lymph nodes. A thorough evaluation, including imaging and further biopsies, may be necessary to rule out this diagnosis.
Tuberculosis: Although less likely, tuberculosis can cause granulomatous reactions and should be considered, especially if the patient has a history of exposure or travel to endemic areas.

Granuloma annulare: A rare skin condition characterized by granulomatous lesions, which could potentially be triggered by the tattoo ink.
Necrobiosis lipoidica: A rare skin condition that can cause granulomatous lesions, although it is not typically associated with tattoos.
Interferon-associated granulomatous disease: A rare condition associated with the use of interferon-alpha, which can cause granulomatous reactions, including skin granulomas.