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INVESTIGATIVE REPORT ActaDV ActaDV Advances in dermatology and venereology Acta Dermato-Venereologica
Eczema in Psoriatico : An Important Differential Diagnosis Between Chronic Allergic Contact Dermatitis and Psoriasis in Palmoplantar Localization
Malgorzata KOLESNIK 1 , Ingolf FRANKE 1 , Anke LUX 2 , Sven R . QUIST 1 and Harald P . GOLLNICK 1
1
Department of Dermatology and Venereology , and 2 Department for Biometrics and Medical Informatics , Otto-von-Guericke University Magdeburg , Magdeburg , Germany
Differential diagnosis of palmoplantar non-pustular psoriasis and chronic allergic contact dermatitis ( ACD ) and the combination of these conditions , termed “ eczema in psoriatico ” ( EIP ), is difficult , especially in cases of isolated involvement . A blind re-evaluation of 63 archived formalin-fixed palmoplantar samples , previously diagnosed clinically as either psoriasis or chronic ACD , was performed . Samples were allocated to histopathological diagnoses of psoriasis , contact dermatitis or EIP . Immunohistological stainings were performed for better characterization . Immunochemistry of EIP revealed features that overlapped contemporarily with psoriasis ( cytokeratin 17 ( CK17 ), Ki67 , interleukin ( IL ) -8 , IL-17 , IL-23 ) and with ACD ( CD1a , major histocompatibility complex ( MHC ) class I , MHC class II , epidermal T-cell subsets ). Surprisingly , a significantly much higher number of dermal CD8 + T cells was found in EIP than in ACD and psoriasis . In conclusion , this study provides insight into the immunohistological differentiation of palmoplantar psoriasis , chronic ACD and EIP .
Key words : eczema in psoriatico ; palmoplantar ; allergic contact dermatitis ; psoriasis ; immunohistology .
Accepted Aug 29 , 2017 ; Epub ahead of print Aug 30 , 2017 Acta Derm Venereol 2018 ; 98 : 50 – 58 .
Corr : Malgorzata Kolesnik , Department of Dermatology and Venereology , Otto-von-Guericke University Magdeburg , Leipziger Str . 44 , DE-39120 Magdeburg , Germany . E-mail : malgorzata . kolesnik @ med . ovgu . de
Differential diagnosis of palmoplantar non-pustular psoriasis and chronic contact dermatitis is often difficult if other characteristic signs and history are missing . Typical histological patterns are often lacking in the palmoplantar localization ( 1 ). Furthermore , these 2 conditions have similar histological features , such as acanthosis , parakeratosis and spongiosis .
The concept of eczematous psoriasis has been discussed previously ( 2 , 3 ). However , there are conflicting results regarding the correlation of psoriasis and contact sensitivity . Some authors have observed an inverse relationship ( 4 ), while others have reported a higher incidence of type IV sensitization only in palmoplantar psoriasis ( 5 , 6 ). Another study noted a positive correlation with the duration of the disease , but not with the site of lesions ( 7 ).
Psoriasis and allergic contact dermatitis ( ACD ) can influence each other ’ s course and clinical picture . It has been shown ( 8 ) that occurrence of the ACD reaction in patients with psoriasis sensitized to nickel is delayed and that it resolves more slowly than in patients without psoriasis . Furthermore , mixed histological and immunohistological patterns have been observed in cases of ACD on top of pre-existing psoriasis , combining both psoriasis and eczema . After self-limitation of an artificially induced ACD reaction , the course of psoriasis was unaltered .
A group of patients with palmoplantar lesions and type IV sensitization , contemporarily showing clinical and histological features of both psoriasis and contact dermatitis , has been indentified in our Department of Dermatology . This constellation ( Fig . S1a – c 1 ) is termed “ eczema in psoriatico ” ( EIP ) ( 9 ).
The aim of the current study was to compare the clinical , histological and immunohistological characteristics of patients with EIP with those diagnosed with palmoplantar psoriasis or ACD alone .
MATERIALS AND METHODS Patients
Patient selection is described in the study flow chart ( Fig . S2 1 ). Intralesional punch biopsies were obtained from patients during routine diagnosis , after obtaining written , informed consent and in accordance with the principles of the Declaration of Helsinki . Two experienced dermatopathologists performed a blind re-evaluation of 132 histopathology sections from the palmoplantar localization stained with haematoxylin and eosin ( H & E ), which had been clinically diagnosed previously as either psoriasis or chronic contact dermatitis . They allocated the samples a diagnosis of psoriasis , contact dermatitis or EIP .
Clinical data and allergy tests were examined retrospectively . Patients presented with well-demarcated scaling palmoplantar erythema . Additional findings , such as erythematous plaques on the elbows , knees or scalp , and oil spots , favoured a diagnosis of psoriasis . Nummular , papulo-vesicular lesions in localizations other than palmoplantar favoured a diagnosis of eczema .
All patients ( except for the control group and 4 patients with psoriasis ) had been investigated previously with the German baseline series of contact allergens ( Almirall Hermal , Reinbeck , Germany ). Patch tests were interpreted according to the guidelines
1 https :// www . medicaljournals . se / acta / content / abstract / 10.2340 / 00015555-2779 doi : 10.2340 / 00015555-2779 Acta Derm Venereol 2018 ; 98 : 50 – 58
This is an open access article under the CC BY-NC license . www . medicaljournals . se / acta Journal Compilation © 2018 Acta Dermato-Venereologica .