Pseudoperforation: An uncommon histologic phenomenon in prurigo misleading for the diagnosis of reactive perforating collagenosis

Prurigo is a common skin condition characterized by vigorous scratching. Although ulceration is not uncommon in prurigo, a perforating-like lesion was not previously reported. In this study we described series of cases of prurigo with perforating-like lesions and discussed its relation to acquired perforating dermatoses. The study included 32 cases, during the period from 2008 to 2013. Clinical data and histological features were recorded and analyzed. The study included 78.1% males and 21.9% females with a mean age of 39.3 ± 5.61 years. History of insect bite was evident in 28.1%, hepatitis C virus infection in 46.9%, and diabetes mellitus in 9.4% of patients. Histologically, well developed lesions showed full thickness epidermal degeneration overlay by a cup-shaped crater. The contents of the crater included collagen and elastic fibers, bacterial colonies, inflammatory cells and necrotic keratin. The dermis showed non-altered collagen, increased vascularity and mixed inflammatory infiltrate. We believe that this pseudoperforation process is a secondary response to vigorous scratching in prurigo patients and not a primary mechanism as occurred in perforating dermatoses. The absence of altered collagen, the presence of full thickness epidermal necrosis and concomitant elimination of elastic fibers are significant histologic clues for differentiation between both conditions.     

IgA autoantibodies in the pemphigoids and linear IgA bullous dermatosis

Please cite this paper as: IgA autoantibodies in the pemphigoids and linear IgA bullous dermatosis. Experimental Dermatology 2010; 19: 648–653. Background: Patients with bullous pemphigoid (BP), mucous membrane pemphigoid (MMP) and pemphigoid gestationis (PG) have IgG antibodies against BP180 and BP230, components of the hemidesmosomes. Patients with linear IgA bullous dermatosis (LABD) have IgA autoantibodies against a 97/120‐kDa protein which is highly homologous to a shedded fragment of the BP180‐ectodomain. Objectives: The aim of our study was to determine the incidence of IgA autoantibodies directed against BP180/BP230 in the pemphigoids and LABD and to determine the antigenic regions that are targeted by IgA autoantibodies. Methods: Utilizing baculovirus‐expressed recombinant BP180 and BP230 proteins, we performed immunoblot analyses for IgA reactivity of sera from patients with BP (n = 30), MMP (n = 10), PG (n = 6), LABD (n = 6) and from control patients with non‐related pruritic dermatoses (n = 8). Results: IgA reactivity against BP180 and/or BP230 was detected in 19/30 of the BP, in 7/10 of the MMP, in 6/6 of the LABD and in 3/6 of the PG sera, respectively, but not in the control group. In all subgroups, the major antigenic site recognized by IgA antibodies was located within the NH₂‐terminus of the BP180‐ectodomain, but only a minority of the sera showed also IgA reactivity against the BP180‐NC16a‐domain. IgA reactivity against the central domain of BP180 was more frequently seen than against its COOH‐terminus. IgA against the COOH‐ and NH₂‐terminus of BP230, respectively, was detected in 6/30 of the BP, 1/10 of the MMP, 1/6 of the LABD and 0/8 control sera. Conclusion: IgA reactivity against BP180 and/or BP230 is a common finding in the pemphigoids.     

Les photoallergies graves

Photosensitivity reactions group together reactions to sunlight, in which the pathophysiology involves the subject's immune system. Concerning exogenous photosensitivity reactions, the photosensitizing molecules responsible for their development have been definitively identified and the reactions are known to be a form of classical delayed hypersensitivity. Nevertheless, while the photosensitizing molecules in idiopathic light eruptions (e.g., polymorphic light eruptions and chronic actinic dermatitis) have not been identified, here, the mechanism is now most often considered to be a delayed hypersensitivity; they can also be IgE-dependent (e.g., solar urticaria). The diagnosis of photosensitivity reactions rests on the patient's history, the appearance of the lesions, their histology and the results of a photo-testing examination. During an exogenous photosensitivity reaction, its severity will depend on the intensity of the reaction, on its evolution to chronic actinic dermatitis or even more on the severity of the specific condition (e.g., polymorphous erythema and hypersensitivity syndrome). Solar urticaria is a serious condition because of its disabling character, the difficulty of treating it and, occasionally, by the existence of general signs or its association with systemic diseases. Hydroa vacciniform (vacciniform cold sores) and pruriginous lesions can lead to the development of particularly ugly scars. More disturbing, vacciniform cold sores can be associated with latent EBV infection and may be complicated by lymphoproliferative disorders involving natural killer cells or by haemolytic syndromes. Chronic actinic dermatitis is surely the most severe photosensitivity reaction because of the severity of the photosensitivity and the risk of its evolution to a lymphoproliferative disorder.     

Epidermal Langerhans cells in actinic prurigo: a comparison between lesional and non-lesional skin

Background  Actinic Prurigo (AP) is a chronic pruritic dermatosis of unknown cause affecting sun exposed skin in defined ethnic groups with characteristic MHC alleles. However, the cutaneous dendritic cells have not been assessed.
Objective  To assess in situ the epidermal Langerhans Cell (LC) status in Actinic Prurigo.
Study design  Fresh skin samples from three AP patients were used to evaluate in situ the epidermal LC, comparing lesional and non-lesional sites in each subject.
Setting  AP patients attending the Dermatology Department at the Hospital M. Gea-Gonzalez in Mexico city.
Methods  Lesional and non-lesional skin samples were taken from each subject to prepare both epidermal sheets and conventional tissue sections. Three markers restricted to LC in epidermis (CD1a, ATPase, MHC-II) were used to quantify the LC per area in epidermal sheets.
Results  Compared to non-lesional skin from the same subject, a significant reduction in the number of LC per area of epidermis was found in lesional skin; with any of the three markers evaluated.
Conclusion  The frequency of epidermal LC decreases importantly in lesional skin from AP patients.     

Pemphigoid gestationis: early onset and blister formation are associated with adverse pregnancy outcomes

Background It is unclear whether clinical features of pemphigoid gestationis (PG), such as timing of onset and severity, may affect pregnancy outcomes or whether the adverse outcomes in pregnancies complicated by PG are related to or worsened by systemic corticosteroid treatment. Objectives To evaluate the associations of adverse pregnancy outcomes with clinical features, autoantibody titre of PG, and systemic corticosteroid treatment. Methods We conducted a retrospective cohort study recruiting 61 pregnancies complicated by PG from the St John’s Institute of Dermatology database which enrolled cases from dermatologists across the U.K., and two tertiary hospitals in the U.K. and Taiwan. Outcome measures included gestational age at delivery, preterm birth, birthweight, low birthweight (LBW, i.e. birthweight < 2500 g), small‐for‐gestational‐age (i.e. birthweight below the 10th percentile for gestational age), fetal loss, congenital malformation, and mode of delivery. Results After controlling for maternal age and comorbidity, decreased gestational age at delivery was significantly associated with presence of blisters (P = 0·017) and disease onset in the second trimester (P = 0·001). Reduced birthweight was significantly associated with disease onset in the first and second trimesters (P = 0·030 and 0·018, respectively) as was also LBW [adjusted odds ratio (95% confidence interval) 13·71 (1·22–154·59) and 10·76 (1·05–110·65), respectively]. No significant associations of adverse pregnancy outcomes with autoantibody titre or systemic corticosteroid treatment were found. Conclusions Onset of PG in the first or second trimester and presence of blisters may lead to adverse pregnancy outcomes including decreased gestational age at delivery, preterm birth, and LBW children. Such pregnancies should be considered high risk and appropriate obstetric care should be provided. Systemic corticosteroid treatment, in contrast, does not substantially affect pregnancy outcomes, and its use for PG in pregnant women is justified.     

Fototerapia en el prurigo nodular. Experiencia propia y revisión de la literatura

Background and objectivePrurigo nodularis is a chronic inflammatory skin disease characterized by highly pruritic nodular lesions that cause constant itching and scratching and significant quality-of-life impairment. It has been described in a range of conditions, including skin diseases (mainly atopic dermatitis) and metabolic, neurological, and psychiatric disorders. The pathophysiological mechanisms are largely unknown. Various modalities of phototherapy have been described as appropriate and safe treatments for achieving clinical control and alleviating symptoms. In this article, we describe our experience with phototherapy in patients with prurigo nodularis.Material and methodsRetrospective observational study of patients who received their first cycle of phototherapy to treat prurigo nodularis between March 2011 and October 2019. Information was collected on epidemiological and clinical characteristics, concomitant treatments, type and duration of phototherapy, maximum dose reached, and response to treatment.ResultsWe studied 44 patients (30 women and 14 men) with a median age of 65.5 years. The most common form of phototherapy used was narrowband UV-B phototherapy (34 cycles, 77.27%) followed by a combination of UV-B and UV-A phototherapy (8 cycles). Response to treatment was considered satisfactory (clearance rate of ≥ 75%) in 24 patients (55.4%).ConclusionsPhototherapy is a suitable treatment for prurigo nodularis in a considerable proportion of patients. It can be used as monotherapy or combined with other treatments.     

The time course of the change in antibody titres in herpes gestationis

The time course of the change in antibody titres was examined postpartum after treatment in two patients with herpes gestationis. The first patient, a 29-year-old woman seen first in the 32nd week of her first pregnancy, had an exudative erythema, and developed an itchy erythema with small tense vesicles on the trunk and legs after delivery in the 40th week of pregnancy. The second patient, a 28-year-old woman seen first in the 28th week of her first pregnancy, had an itchy exudative erythema, small tense vesicles and crusts on the legs. After a Caesarean section in the 40th week of pregnancy performed because of cardiac complications in the fetus, the skin lesions extended to the trunk and extremities. Direct immunofluorescence revealed linear depositions of IgG and C3 at the basement membrane zone (BMZ) and indirect immunofluorescence was positive at the epidermal side of the BMZ in 1 mol/L NaCl-split skin in both cases. In patient 1, prednisolone, 20 mg/day, administered 4 months after delivery, gave rapid improvement (within 1 week) of the skin lesions; in patient 2, minocycline, 200 mg/day, administered 2 weeks after delivery, gave improvement within 2 weeks. Immunoblotting against epidermal extracts revealed the presence of antibodies directed to the 180 kDa bullous pemphigoid antigen in both sera. Indirect immunofluorescence and immunoblot were positive for at least 2 months in patient 1 and for 5 months in patient 2 after disappearance of the skin lesions.