What is guttate psoriasis?
Guttate psoriasis is a variant commonly seen in adolescents and young
adults. It is characterized by small, tear-shaped papules and plaques. The term
“teardrop” comes from the Latin ” gutta “, meaning drop.
This variant of psoriasis usually develops against the background of
streptococcal pharyngitis, the treatment of which with antibiotics leads to
improvement or even resolution of psoriasis.
What role does the hereditary factor play in the development of psoriasis?
Although no specific genetic defects have been identified, psoriasis is classified as a genetically determined disease. Family pedigree data allow us to regard psoriasis as a disease with an autosomal dominant type of inheritance with partial penetrance. Environmental factors probably play a provoking role in the clinical manifestation of psoriasis. The most convincing significance of external factors is demonstrated by the development of acute guttate psoriasis against the background of streptococcal infection of the pharynx.
If one of my relatives has psoriasis, what is the likelihood that I will get psoriasis?
Studies have shown that almost 5% of first-degree relatives of people with psoriasis also have this dermatosis, compared with 1.2% of those who do not have direct relatives with psoriasis. If one of the siblings has psoriasis, the other has psoriasis in 16% of cases, provided that one of the parents is sick. If both parents and one of the siblings are sick, then the other psoriasis occurs in 50% of cases. In the presence of psoriasis in one of the twins in the second, it occurs in 20% of cases, and if the twins are identical, in 73%. The lack of 100 percent agreement in the occurrence of psoriasis in monozygotic twins (they have the same genetic set) indicates the influence of environmental factors.
How do nail plates change in psoriasis? What
are the most common changes?
A careful study of the nail plates should be carried out when examining any
dermatological patient, especially if he has psoriasis-like rashes.
Characteristic nail lesions occur in 25-50% of people with psoriasis and
present as pitting, discoloration, onycholysis , subungual hyperkeratosis, and
deformity. The most common are punctate lesions, which are characterized by
small discrete depressions of the ulnar surface. Rounded areas of discoloration
of the nail beds resemble oil stains and are often visible under the nail
plate. The nail may thin, become brittle at the free edge, and separate from
the nail bed ( onycholysis ), or thicken in association with subungual
deposits. There are also lesions in the form of furrows, scallops, or obvious
deformities.
What is the Koebner phenomenon and the Auspitz
sign in a patient with psoriasis?
The isomphoric or Koebner phenomenon is the development of psoriasis at
the site of a physical injury to the skin (scratches, surgical wounds,
sunburn). This phenomenon also occurs with lichen planus and filiform lichen.
Patients with psoriasis should be warned about this phenomenon, especially if
they intend to undergo procedures associated with skin trauma (tattooing). The
Auspitz symptom is the appearance of pinpoint bleeding when scraping
psoriatic elements. Bleeding is due to thinning of the epidermis. Remember that
it is not permissible to detect the presence of these symptoms directly on the
patient.
How does seborrheic dermatitis manifest itself?
Seborrheic dermatitis is a chronic dermatitis localized in seborrheic areas and is characterized by well-defined lesions covered with greasy yellow scales. The scalp is almost always involved in the process. The face is usually also affected; while erythematous-squamous elements are localized on the medial part of the eyebrows, glabella (glabella) and in the nasolabial folds. Blepharitis and conjunctivitis and lesions of the ears (external auditory canal) are common. The visible scaling known as dandruff is probably a worn-out form of seborrheic dermatitis.