Linear IgA Dermatosis Clinical Presentation

Some patients note a prolonged period of prodromal itching or transient pruritus or burning before lesions appear. Patients with ocular manifestations may complain of pain, grittiness, or discharge.

Bullae may be chronic, or lesions may appear acutely, as seen in drug-induced disease. Rash latency in vancomycin-induced cases of linear IgA dermatosis ranges from 1-13 days after the first dose. Review of medication exposures and delineation of the drug timeline are crucial in identifying potential inciting agents.

The classic primary lesions of linear IgA dermatosis are clear and/or hemorrhagic round or oval vesicles or bullae on normal, erythematous, or urticarial skin. Cutaneous manifestations may also include erythematous plaques, blanching macules and papules, or targetoid erythema multiforme–like lesions. The diagnosis is not dependent on the presence of vesicles and/or bullae and a morbilliform variant has been described.^[6]

Bullae may be discrete or arranged in a herpetiform pattern, often described as the cluster of jewels sign. Alternatively, vesicles and bullae may be seen at the edge of annular or polycyclic lesions, the appearance of which has been described as the string of beads sign (see the image below).

The distribution of linear IgA dermatosis differs between adults and children. Lesions in children are typically localized to the lower abdomen and anogenital areas with frequent involvement of the perineum (see the image below). Other sites of involvement include the feet, the hands, and the face, particularly the perioral area. In adults, the trunk and the limbs are most commonly affected. In adults, involvement of the perineum and the perioral area is less frequent than in children. Lesions in both children and adults may be distributed symmetrically or asymmetrically. Dermatitis herpetiformis–like involvement of the extensor surfaces of the knees and the elbows is seen infrequently. Crusts, excoriations, erosions, or ulcers may be present.

Oral manifestations are common in children and adults with linear IgA dermatosis. Oral lesions include vesicles, ulcerations, erythematous patches, erosions, desquamative gingivitis, or erosive cheilitis, and they may precede skin lesions.^[7]

Both children and adults frequently complain of ocular symptoms, such as grittiness, burning, or discharge. Ophthalmologic findings even in the absence of ocular complaints may include subconjunctival fibrosis, shrinkage of the fornices, symblepharon formation, and cicatricial entropion with trichiasis (see the image below).^[8]

The list of agents implicated in linear IgA dermatosis continues to grow, especially with regard to medications. Many patients report prodromal events, such as illnesses or ingestion of drugs. In absent large series or a preponderance of case reports, only a subset of cases have identifiable causes. Gluten-sensitive enteropathy is not associated with linear IgA dermatosis. Various causes are discussed as follows:

• Seventeen case reports have implicated vancomycin in linear IgA dermatosis. Of all reported causative drugs, it is the best-documented agent in the literature.^[9] Other potential triggers and include the following: amiodarone, ampicillin sodium, captopril, cefamandole nafate, cyclosporine, depot sulfonamide, diclofenac, glibenclamide, interferon gamma and interleukin 2, iodine contrast agent, lithium carbonate, penicillin sodium, phenytoin sodium, somatostatin, sulfamethoxazole/trimethoprim, sulfisoxazole, topical sodium hypochlorite (1), moxifloxacin, amoxicillin-clavulanate, and vigabatrin.
• The development of linear IgA bullous dermatosis has been reported following influenza vaccination in a 54-year-old woman.^[10]
• Preceding illnesses, such as typhoid, brucella, tuberculosis, antibiotic-treated tetanus, varicella, herpes zoster, Paecilomyces lung infection, gynecologic infections, and upper respiratory infections, have all been reported in association with linear IgA dermatosis. The significance of these associations is uncertain. Their potential role in stimulation of the IgA mucosal system has yet to be elucidated.
• Linear IgA dermatosis associated with malignancy has been reported in as many as 5% of cases. Lymphoproliferative malignancies, specifically Hodgkin disease, non-Hodgkin lymphoma (eg, following stem cell transplantation),^[11] and chronic lymphocytic leukemia have been described.^[12] Linear IgA dermatosis has also been reported with solid tumors, such as bladder carcinoma. Other associated malignancies include polycythemia rubra vera, plasmacytoma, multiple myeloma, ocular melanoma, squamous cell carcinoma of the esophagus, breast carcinoma, uterine carcinoma, eccrine carcinoma, metastatic squamous cell carcinoma, colon carcinoma, thyroid carcinoma, retroperitoneal carcinoma, metastatic hypernephroma, pancreatic carcinoma, and hydatidiform mole. The validity of the association between linear IgA dermatosis and malignancy remains to be proven.
• Because linear IgA dermatosis is itself an autoimmune disease, an association with other such disorders is interesting despite proven causality. Cases have been described in association with systemic lupus erythematosus, dermatomyositis, rheumatoid arthritis, polymyalgia rheumatica, hypothyroidism, chronic hepatitis, Crohn disease, ulcerative colitis, multiple sclerosis, acquired hemophilia, and IgA nephropathy. Again, these associations may be coincidental.
• Linear IgA dermatosis in children has been reported in association with human leukocyte antigen B8 (HLA-B8), but the significance of this finding is unknown.
• Pancreatic lipase deficiency has been reported once in association with linear IgA dermatosis.