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Wyprysk z hiperkeratozą - Objawy, Diagnoza i Leczenie
Pathophysiology
The skin is composed of three layers: the epidermis, the dermis (composed of the superficial papillary and deeper reticular dermis), and the hypodermis. The skin has structural differences among the different areas of the body in terms of epidermal and dermal thickness, distribution of appendages, and pigmentation. The epidermis is composed of multiple layers of maturing keratinocytes: the basal layer (stratum basale), the squamous layer (stratum spinosum), the granular layer (stratum granulosum), and the cornified layer (stratum corneum). This stratified epithelium is in a constant process of self-renewing and exfoliation that takes 20-40 days to complete. The cells in the outer layer are the most differentiated in the keratinocyte line, composed almost entirely of keratin lamels of high molecular weight, and those are the ones that undergo desquamation, completing the maturation cycle.
When the epidermis is exposed to repetitive injury, it usually elicits an increased proliferative rate of the keratinocytes and accelerates their maturation. Keratinocytes also tend to produce more keratin, thus increasing the stratum corneum's thickness.
Genetic mutations resulting in hyperkeratosis is seen in ichthyoses and keratoderma. There are several damages in keratin-encoding genes such as KRT1 and KRT10, which cause defects in keratin structure. Defective keratin causes irregular aggregates of intermediate filaments, which leads to cellular collapse and blistering. The barrier function is then compromised, and the skin reacts with compensatory hyperproliferation, which leads to hyperkeratosis.
History and Physical
Hyperkeratosis is a histopathological term defining a thickened stratum corneum and may be present in many different skin conditions, with many possible overlaps. History and clinical evaluation are key, and the main goal is to collect as much information as possible and discern which cases require a histopathological diagnosis to direct the most appropriate treatment.
The history comprises the age of the patient, family history, exposure to toxic substances, drugs, occupational duties, anamnesis of the current lesion, concomitant pathologies, and treatments. In those patients where the diagnosis was already established, it is appropriate to reevaluate it, monitor progression and complications following the treatment.
The physical examination must be thorough to exactly understand the extent of the disease. Except for localized disease, it is important to inspect the entire skin surface, including scalp, eyelids, ears, perineum and genital mucosa, hair, and nails. The lesion should be described in terms of color, texture, shape, and distribution. Surrounding skin should be examined as well to detect the presence of generalized xerosis (dryness), seborrhea, hyper or hypohidrosis (sweating), texture, photoaging such as lentigines, actinic purpura, rhytides.
Small folliculocentric keratotic nodules can be found in cases of keratosis pilaris, where papules are centered on small hair follicles, and it can be associated with erythema. On close examination, it is possible to recognize a small coiled hair beneath the papule formed by a keratin plug.
Scaling is an important finding in cases of hyperkeratosis. Scales may be described as soft, rough, greyish, bran-like, and so on. Crusts should not be confused with scale as it is the result of dried fluid on the epidermis (serum, blood, pus, or a combination of those) and not thickening of the epidermis. Lichenification is a thickening of the skin and results from chronic injuries such as repetitive scratching. It is present in most chronic eczematous or neurogenic processes.
HYPERKERATOZY – rodzaje i różnicowanie cz.2
- odciski
- modzele
- nadmierne rogowacenie i zespół pękających pięt
- rogowiec
Zmiany będące reakcją obronną skóry na bodźce zewnętrzne. Powstają na skutek nadmiernego wytwarzania komórek warstwy rogowej naskórka. Powstaje bariera uniemożliwiająca fizjologiczną migrację nowych komórek, a co za tym idzie dochodzi do pozostawania korneocytów w niższych warstwach skóry.
Odciski są wyniosłymi zgrubieniami naskórka o kształcie okrągłym, podłużnym lub nieregularnym. Cechą wyróżniającą odciski jest obecność rdzenia, czyli twardego czopu rogowego, zlokalizowanego najczęściej centralnie.
Trzpień odcisku często sięgając głęboko (nawet do okostnej), drażni zakończenia nerwowe dając uczucie bólu.
Introduction
Hyperkeratosis refers to the increased thickness of the stratum corneum, the outer layer of the skin. Stratum corneum is composed of multiple layers of keratinocyte bodies that, during maturation, produced keratin and subsequently have lost their nucleus and cytoplasmic organelles. The result is a basketweave appearance of anucleate keratinocytes that protect the underlying cells during maturation.
Hyperkeratosis is subclassified as orthokeratotic or parakeratotic. Orthokeratotic hyperkeratosis refers to the thickening of the keratin layer with preserved keratinocyte maturation, while parakeratotic hyperkeratosis shows retained nuclei as a sign of delayed maturation of keratinocytes. Hyperkeratosis can be associated with dyskeratosis. It represents a premature (keratinocytes that are located below the granular cell layer) or abnormal keratinization of individual keratinocytes.
Hyperkeratosis, associated with other abnormalities in the skin biopsy, can be a key to the final histological diagnosis. Epidermal hypertrophy is a benign alteration of the skin that presents with acanthosis (increased thickness of the keratinocyte layers) and hyperkeratosis.
