The term granulomatosis indicates a group of diseases which is basically characterised by a pathogenesis of inflammation, a slow, progressive evolution, and a consistent tendency to become chronic. These can be observed as individual lesions, multiple lesions, lesions spread throughout an organ or system or systemic multifocal spread. It is difficult to reach an aetiological, pathogenic, and clinical finding for this group of diseases [1].
Clinical forms are characterised by a systemic multiregional onset and subsequent slow evolution with preferential localisation in a certain region or organ. For example, sarcoidosis and Crohn’s disease [2]. Other clinical forms are characterised from the early stages by localisation and stable evolution in an individual organ, such as foreign body granulomatosis and some forms of chronic dermatosis [3]. A further aetiological classification identifies infectious and non-infectious forms of granulomatosis. The infectious forms of granulomatosis include systemic tuberculosis, organ tuberculosis, and tertiary syphilis. The non-infectious granulomatoses fall within a group of diseases that are rather diverse and difficult to diagnose; they are basically characterised by a slowly progressing immunological and inflammatory pathogenetic matrix against as yet unknown exogenous factors [4, 5]. Finally, granulomatosis can be divided topographically based on the position or region of the body that is affected. Specifically, Authors consider orofacial granulomatosis (OFG) diseases, characterised by individual localised granulomas or the formation of multiple granulomas [6].
The clinical progression of all forms of OFG is typically chronic with possible remissions followed by subsequent flare-ups. In many cases they present with localised lesions and completely asymptomatic. Forms of OFG present clinical, evolutionary and, more importantly, histopathologic features that are remarkably similar to systemic granulomatous diseases, such as Crohn’s disease. However, none of these clinical forms are accompanied by the intestinal symptoms and signs typical of Crohn’s disease. All oral and maxillomandibular regions may potentially be affected. Lesions on the lips, the body of the tongue, oropharynx, palate, and gingival mucosa occur with varying frequency [7]. Although lacking in specific characteristics, these lesions are characterised by the constant swelling of the affected tissues. Under clinical observation oedema, inflammatory infiltrate lesions, granulomas, and erythematous and ulcerated areas may by present. Diagnosis is often difficult and a combination of systemic clinical data, localised signs and symptoms, and microscopic examinations need to carefully correlated [8].
Amongst the non-infectious OFG, we find MRS and its monosymptomatic, clinical variant represented by MCG, which was described for the first time by Miescher in 1945 [9]. MRS is characterised by a clinical triad of oedema on the lips, which rarely even affects parts of the face, a plicated or fissured swollen tongue, and relapsing facial nerve paralysis. At least two of these clinical presentations are required for a diagnosis of MRS [9]. It is considered to be a rare disease and generally shows no particular preference for ethnic background, age, or sex. However, there are some epidemiological data which state that is a slightly higher prevalence in females [10].
MCG typically affects only the lip region and is characterised by chronic, sometimes recurrent, swelling, often in the absence of any other symptoms and affects the lips thickness to varying degrees. The upper lip is more frequently affected, although both lips can be afflicted. Swelling and oedematous thickening often make it difficult to move the lips, consume solid or liquid food, and produce or utter speech sounds. The aesthetic aspects in more severe cases should be considered [11, 12].
In the early stages of MCG, histological characteristics may be non-specific with the presence of oedema, ectasia of arteries, veins and lymphatic vessels, inflammatory angiogenesis, and perivascular infiltrates of lymphocytes, plasma cells and histiocytes. In the later stages of the disease, granuloma formations are present with multinucleate giant cells of the langhans type, without signs of vascular necrosis or caseous necrosis [8]. The presence of granulomas is characteristic, although their absence does not preclude a diagnosis of MCG. Considering that a differential diagnosis applies to some lesions on the lips, a diagnosis of MCG can be correctly formulated by carefully assessing the patient history, the duration of the lesions on the lip, and the correlations of clinical and histopathologic features [11, 12].
Numerous treatment protocols and experiences have been described and documented in the literature. The most commonly described treatments are pharmacological treatments with local, systemic and intralesional steroid therapies. The most commonly used pharmaceuticals are systemic prednisone, intralesional triamcinolone, and combinations of antibiotic and steroid treatment. Immunosuppressive drugs have also been used, including methotrexate, monoclonal antibodies such as infliximab and adalimumab, and systemic antibiotics such as tetracycline and metronidazole. However, all of the treatments that have been documented in scientific literature have had variable immediate results and, above all, are short lasting in the long term. Reductive surgical treatments have shown to have immediate therapeutic success, but even these treatments have shown early and late tendencies towards relapse [13, 14].
This clinical case of MCG was treated with low-level laser therapies (LLLT), which are now more correctly known by the name photobiomodulation (PBM). It has been widely documented in the literature that localised PBM treatments have proven to have significant anti-inflammatory properties, facilitate tissue repair, and control painful symptoms [15, 16].