LABD in adults can have varied presentation, making it difficult to distinguish from other autoimmune vesiculobullous diseases such as bullous pemphigoid (BP). Patients may present with scattered, tense bullae on a background of non-inflamed skin, while others may develop a more herpetiform appearance to their lesions with prominent erythema beneath the vesicles or bullae. The lesions typically have a widespread distribution and usually involve the trunk and extremities but can also involve the scalp, genital area or face. Some patients may have to expand annular vesiculobullous plaques or even a presentation mimicking toxic epidermal necrolysis (TEN). In chronic bullous disease of childhood, the classic clinical presentation includes annular erythematous lesions with a ring of vesicles, commonly referred to as a "crown of jewels" or "string of pearls." In children, the lesions most commonly occur on the abdomen, lower back, thighs, groin area, and around the eyes and mouth. The "crown of jewels" or "string of pearls" is less commonly observed in the adult form.

Like many other autoimmune vesiculobullous disorders such as pemphigus vulgaris (PV), BP, and cicatricial pemphigoid (CP), LABD can also have mucous membrane involvement in about 50% of patients, making the examination of mucous membrane surfaces such as the oral mucosa, conjunctivae, nares, and genital areas an important component of a complete examination in patients with suspected vesiculobullous disorders. Like CP, the mucosal involvement in LABD may result in significant scarring. The most commonly involved mucosal surfaces are the oral mucosa and conjunctiva. Interestingly, drug-induced LABD, particularly drug-induced LABD secondary to vancomycin, tends to be much more severe and may mimic toxic epidermal necrolysis (TEN) and may even have a positive Nikolsky sign.

There have been reports of atypical variants/presentations of LABD including an eczematous form, prurigo nodularis-like form, urticarial form, morbilliform presentation, and even a seborrheic dermatitis-like presentation of LABD.

Both the adult and childhood form of LABD can vary symptomatically from completely asymptomatic, to mild or severe pruritus or burning sensation.

By far, the most important aspect of the workup for LABD is obtaining biopsies for histopathological examination. The clinician should obtain two punch biopsies, one for routine hematoxylin and eosin (H and E) staining and the other for direct immunofluorescence (DIF). The biopsy for routine H and E should be obtained from an actual skin lesion, while the sample for DIF should be obtained from the perilesional skin. Additional workup may include indirect immunofluorescence (IIF) to test for the presence or absence of circulating IgA anti-basement membrane zone antibodies, which may be found in up to 70% of LABD patients but are not found in patients with DH. In the lamina lucida subtype of LABD, these antibodies will adhere to the roof of a salt-split skin test (epidermal side), while in the sub-lamina densa variant the antibodies will adhere to the floor (dermal side).

A thorough history and physical examination may significantly help guide the clinician towards a diagnosis of LABD, even before the pathology report returns. A complete review of medications, including all over-the-counter medications along with vitamins and mineral supplements, is crucial to help rule out drug-induced LABD.[9][10][11]

Multiple different treatment options have arisen for LABD since its original discovery in the 1970s, but the most commonly used medication to treat the disorder is oral dapsone. Fortunately, the disease is exceptionally responsive to dapsone and improvement can be seen within 2 to 3 days of drug initiation. Relatively low doses of dapsone are required for successful disease management, with an average of 100 mg daily for adults, while children generally require 1 to 2 mg/kg per day. Patients on dapsone should be monitored closely for development of hemolytic anemia, agranulocytosis, dapsone hypersensitivity syndrome, leukopenia, cholestatic jaundice, peripheral neuropathy, and nephrotic syndrome. Occasionally, patients may also require adjunctive administration of oral corticosteroids to gain initial control of the disease. Sulfapyridine remains as another treatment option.[12][13]

Interestingly, multiple antibiotic therapies, such as the tetracycline class, dicloxacillin, and trimethoprim-sulfamethoxazole, have also proven to be beneficial in controlling the disease but no specific underlying infectious etiology has ever been discovered. In patients with drug-induced LABD secondary to vancomycin, patients may benefit from discontinuing the vancomycin, but then adding a new antibiotic such as doxycycline with the added benefit of relatively similar microbial coverage, and it may also serve as a potential treatment for the patient's LABD. Nicotinamide 1.5 g per day may be beneficial as an adjunctive treatment.

The differential diagnosis for LABD should include other vesiculobullous diseases such as dermatitis herpetiformis, bullous pemphigoid, epidermolysis bullosa acquisita, bullous impetigo, or pemphigus vulgaris. There have also been numerous reports of LABD mimicking erythema multiforme and TEN. Dermatitis herpetiformis has very similar findings on immunohistochemical staining, with the main difference being the granular deposition of IgA, instead of linear deposition as in LABD. Bullous pemphigoid is characterized by linear deposits of IgG along the epidermal basement membrane zone. Unfortunately, at times there can be a mixed linear deposition of both IgG and IgA at the basement membrane which creates a diagnostic conundrum. Different options exist as far as classifying this specific deposition pattern as either bullous pemphigoid or LABD.

The prognosis for both LABD and the pediatric variant, "chronic bullous disease of childhood" are both generally promising. Spontaneous remission may occur in 30% to 60% of adult patients, usually only occurring after years of active disease. In children, the disease tends to spontaneously remit within 2 to 4 years after onset, which is exceptionally reassuring for parents. Since systemic therapies may be masking a patient's spontaneous remission, the general recommendation is to periodically attempt to withdraw these medications to evaluate for the unknown remission of the disease.

Drug-induced LABD also has a good prognosis with most cases remitting within 2 to 6 weeks after the inciting medication is discontinued.

Consultations for a patient suspected of a vesiculobullous disease should be directed toward a dermatologist. In a patient with a known diagnosis of linear IgA bullous disease with the suspected associated gastrointestinal disease, autoimmune disease, or malignancy, the patient should be referred to the respective specialists.

• Always consider drug-induced LABD in adults with a new diagnosis of LABD.
• Chronic bullous disease of childhood has a reassuring prognosis as most of the cases spontaneously resolve within a few years of onset.
• Vancomycin is the most common cause of drug-induced LABD.
• Loose associations exist between LABD and malignancy, gastrointestinal disease, and autoimmune disease.
• Classic histopathological findings on H and E include subepidermal split, rich neutrophilic infiltrate +/- eosinophils.
• Classic DIF finding is linear IgA deposited along the basement membrane zone.
• Classic IIF finding is circulating IgA antibodies deposited on the epidermal side of salt-split skin (lamina lucida subtype) or circulating IgA antibodies deposited on the dermal side of salt-split skin (sub-lamina densa subtype).
• Vancomycin-induced LABD is associated with a severe presentation of the disease that may mimic TEN. 
• At least 2 initial biopsies should be obtained, one of an actual lesion for H and E and another from a perilesional area for DIF.
• The most commonly used treatment is dapsone.

LABD has a diverse presentation and has many causes. The disorder is best managed by an interprofessional team that includes pharmacists. Consultations for a patient suspected of a vesiculobullous disease should be directed toward a dermatologist. In a patient with a known diagnosis of linear IgA bullous disease with the suspected associated gastrointestinal disease, autoimmune disease, or malignancy, the patient should be referred to the respective specialists.

In most cases, discontinuation of the offending agent will help reverse the condition, but it may take time.