Patients often present with a relatively abrupt onset of asymptomatic red, yellow, brown, or skin-colored papules or nodules, which are occasionally pustular and symmetrically distributed predominantly on facial skin. The lower eyelids are most characteristically involved, and involvement of forehead, cheeks, nose, upper lips, ears, chin, or neck is common.[4] Extra facial involvement is uncommon but has been reported in some cases, including on the trunk, extremities, and genital skin.[2] Co-morbidities have not generally been reported in association with LMDF.

Symmetrically distributed inflammatory papules or papulopustules with histologically confirmed granulomatous inflammation should lead to consideration of the diagnosis. A background of erythema, telangiectasias, or a propensity for flushing would favor a diagnosis of granulomatous rosacea, as would exacerbation of disease by such triggers as steroid use, sunlight, alcohol, or spicy foods.[1][5] Exclusion of an infectious etiology by histochemical stains (e.g., Ziehl-Neelson stain) and/or tissue cultures is often prudent, although the sensitivity of these tests is imperfect. Many authors have included serum calcium and angiotensin-converting enzyme levels in their workup, with or without chest X-ray and ophthalmologic exam, to help exclude sarcoidosis.[2] Serologic assays for tuberculosis and treponemal infection may also be considered.[4]

The evidence for treatment of LMDF is limited to case series and retrospective reviews and should be considered even though the disease course is usually self-limited. This disease tends to be poorly responsive to topical or systemic therapies that are first-line for granulomatous rosacea. The efficacy of oral tetracyclines is poor, whereas the response to isotretinoin is mixed.[8] In one series, patients demonstrated a better response to oral prednisolone (administered at starting doses of 10mg daily) or oral dapsone (100mg daily). The combination of these two agents seemed to be especially effective, including in patients who had failed monotherapy with either alone. In the same series, the combination of oral dapsone with topical tacrolimus was reported to produce an excellent response in 7 of 7 patients.[1] Other studies also report good responses to systemic corticosteroids.[11] Early, effective treatment may reduce the risk of significant scarring.

As discussed, cutaneous tuberculosis or other infections, especially fungal, mycobacterial, treponemal, or leishmanial, should be considered. A bilateral, symmetric, relatively rapid onset in an otherwise well patient without associated symptoms makes an infectious etiology less likely. If an infection is excluded, the clinical and pathologic differential may include granulomatous rosacea at one end of the spectrum, and cutaneous sarcoid at the other.

Like LMDF, granulomatous variants of rosacea can present with bilateral, symmetric facial papules with similar morphology. There is considerable histologic overlap, including relationship to pilosebaceous units, although LMDF may have larger granulomas that are more prone to caseation necrosis, and is not expected to have actinic damage, vascular dilation, or the presence of Demodex mites.[5] The clinical features and course may help discriminate these entities. Notably, LMDF occurs in the absence of phymatous changes, ocular involvement, or vascular manifestations of rosacea such as background erythema, flushing, or telangiectasia. Compared to rosacea, LMDF tends to affect adults at a younger age, including some cases in adolescents and exceptional cases in children and may affect men more commonly.[5] The involvement of eyelids, upper lips, and neck is more common in LMDF, and extra facial involvement can occur.[2] LMDF is more likely than rosacea to spontaneously resolve within several years, but more prone to significant pitted scarring. As discussed above, LMDF responds somewhat differently to treatment than rosacea, being less successfully treated with antibiotics and more successfully treated with corticosteroids.[1][2][4]

Sarcoidosis should be excluded by clinical and/or laboratory investigations, especially in those whose disease is slow to regress or shows progression.[6] While LMDF has also been proposed as a possible forme fruste of sarcoid, it lacks clinical, laboratory, or radiographic evidence of extracutaneous manifestations, and does not progress to visceral involvement. Histologically, the granulomatous infiltrate is more prone to caseation and often associated with pilosebaceous units.[2] Deep-seated, annular, or solitary lesions, or lesions involving the scalp or only a part of the face, should raise concern for the possibility of sarcoidosis.[6]

Other facial granulomatous disorders, including granulomatous perioral dermatitis, may also be considered in the differential.

LMDF is a skin-limited disease. The natural history of the disease is usually spontaneous involution over months to several years, with a mean duration of 18 months in one series.[7]

The primary long-term complication is facial scarring, which can be significant and disfiguring. Early treatment may prevent or minimize significant scarring.[1]

Unlike rosacea, there are no documented lifestyle risk factors for LMDF. Once the diagnosis is made after appropriate workup as above, patients should be reassured about the skin-limited nature of the disease, the expected eventual resolution, and the potential for treatment to reduce the risk of permanent scarring.

Patients with LMDF should be managed by an interprofessional team approach in order to improve outcomes. Primary care providers and dermatologists will be involved. Certain treatment options, including dapsone and systemic corticosteroids, require careful education and monitoring, which should be reinforced by and coordinated with nursing and pharmacy professionals. (Level 5)