Generality
Scalp psoriasis is an inflammatory disease that causes plaque lesions, with redness, slight occasional itching and flaking similar to dandruff.
Psoriasis of the scalp develops due to the malfunctioning of the immune system, which induces a very rapid proliferation of the epidermis cells (the turn-over occurs in 3-7 days, instead of every 28 days). Many people experience a worsening of the disorder coinciding with painful or stressful events, or after traumas (Koebner's phenomenon) or infections that can cause a lowering of the immune defenses.
In the presence of symptoms of psoriasis of the scalp, it is always correct to contact a doctor who can identify the type and severity of the condition and indicate, consequently, the most appropriate therapy for one's case.
Psoriasis: key points
- Psoriasis is a chronic, non-contagious disease that can involve the skin, joints, nails and the perianal region.
- The pathological process is characterized by hyperproliferation of keratinocytes and is associated with inflammation of the epidermis and dermis. This reaction is responsible for the appearance of well-circumscribed lesions (plaques), erythematous (reddish) and covered with silvery-gray scales. The causes of psoriasis have not yet been fully clarified, but a role is certainly played by the immune system.
- In most cases, psoriasis occurs with papules and plaques with clear margins. These erythematous and roundish spots are covered by scales. Such lesions may be asymptomatic or cause a mild occasional itching, but the aesthetic implications may be important.
- The diagnosis of psoriasis is based on the appearance and distribution of the lesions.
- The treatment of psoriasis is based on the use of emollients, topical drugs (analogues of vitamin D, retinoids, tar, antraline and corticosteroids), phototherapy and, in the most serious forms, systemic drugs (methotrexate, cyclosporine or biological drugs).
Causes and risk factors
The scalp is affected in 75% of psoriasis patients.
The causes of the disorder are not yet fully known; in this regard, it is believed that an environmental triggering factor evokes an autoimmune inflammatory response, on which the subsequent accelerated cell renewal at the level of the epidermis depends. These cells produced in excess accumulate on the surface of the scalp, causing the appearance of psoriatic plaques .
Scalp psoriasis can occur in female and male subjects, at any age; often appears following the intervention of triggering agents, such as:
- Traumas (mechanical, chemical, allergic or other);
- Infections (eg beta-hemolytic streptococcus, HIV etc.);
- Sunburns;
- Hormonal changes;
- Alcohol and smoking abuse;
- Psycho-physical stress;
- Bad eating habits;
- Some medications (in particular: beta-blockers, chloroquine, lithium, ace-inhibitors and interferon-alpha).
Familiarity is also frequent: several genes are potentially involved in the onset of the disease and the children of a parent with psoriasis are more likely to suffer from it.
During the summer period, in case of correct exposure to the sun's rays, the symptoms of psoriasis of the scalp regress due to the regenerating action of vitamin D, while during the winter atmospheric agents further stress the skin affected by these irritations.
Koebner's phenomenon: what is it?
Koebner's phenomenon, also called reactive isomorphism, is an inflammatory reaction that occurs, after a lot of time, in areas affected by traumas even minimal.
In the patient with psoriasis of the scalp, this phenomenon can induce and worsen the disease: for this reason, it is recommended the importance of absolutely not removing the scales with mechanical means, such as combs or nails.
Signs and symptoms
Scalp psoriasis manifests itself in different forms . The dimensions of the individual patches are, for example, extremely variable (from a few millimeters to several centimeters), as well as the location, the evolution and the color tone. The lesions can also be asymptomatic or itchy.
The most frequent manifestation of the disorder is the diffuse redness of the scalp, with slight occasional itching (note: the desquamation can be scarce, but irregular erythematous areas are visible).
Other common symptoms include:
- Flaking similar to dandruff, with the production of gray-whitish flakes on the scalp, around the hair shaft and on clothing;
- Appearance of erythematous (reddish) and desquamating plaque lesions on the scalp;
- Dryness of the scalp that presents an increased tendency to damage and bleed;
- Burning sensation or pain;
- Increased hair loss.
In some cases, psoriasis can extend to "calotta", that is to the whole scalp, also involving the ears, the area above and behind the ears, the lobes, the nape, the forehead and the hairline. Given the location of the lesions, therefore, even if the symptoms associated with the disease are minimal, the aesthetic implications may be important.
At the level of the scalp, the lesions appear gradually and are characterized by a chronic-relapsing course: periods of remission in which the symptomatology is attenuated or disappears completely can be alternated with others in which the manifestations become more severe.
Psoriasis of the scalp or dandruff?
In some cases, it can be difficult to distinguish dandruff from psoriasis. In fact, both conditions affect the scalp and share similar symptoms, such as itching, redness and peeling.
In general, however, some differences can be observed upon visual examination of the scalp.
In psoriasis, the scales rise spontaneously, revealing a bright red scalp underneath for inflammation. The material produced by the desquamation is silvery-white in color, as well as being larger and larger (thick and thick).
In dandruff, however, the scales tend to be small and fine, yellowish or whitish in color.
Psoriasis usually affects other areas of the body, so the elbows, knees, chest and fingers should be examined to check for the typical lesions of the disease; in fact, if you are suffering from psoriasis of the scalp, these areas could also be affected in a similar way.
In any case, it is advisable to contact your doctor to correctly diagnose and properly treat the exact underlying condition.
Possible complications
The severity of scalp psoriasis varies from person to person: in some cases, only a few areas have scales similar to dandruff and the disease only causes slight discomfort; at other times, eruptions occur that cover large areas and are difficult to treat .
Psoriasis of the scalp can also extend over the forehead, the back of the neck and around the ears. Persistent lesions can lead to thinning of the hair or even loss of the same.
Regardless of severity, scalp psoriasis can affect the quality of life of those affected, especially in very "visually" obvious cases, and can lead to negative psychological reactions, even of a certain importance.
Diagnosis
The diagnosis of psoriasis can generally be formulated starting from the examination of the patient's scalp appearance and the distribution of the lesions. Dermoscopy shows typical vascular alterations, which make it possible to differentiate psoriasis from seborrheic dermatitis, with which it is often confused clinically.
The diagnosis of psoriasis of the scalp also includes the collection of the anamnesis with the evaluation of the possible familiarity, taking into account the genetic basis of the disease and any changes that have recently occurred in the life of the patient that may have triggered it.
Rarely, it is necessary to perform a biopsy for the microscopic histological examination of a small sample of skin tissue, in order to exclude other conditions.
Treatment
The therapeutic options for scalp psoriasis are numerous; these are not conclusive, but aimed at keeping the disease under control.
Depending on the severity of psoriasis, topical treatments (ie the application of creams and lotions directly on the scalp), phototherapy and / or systemic drugs can be used . However, it should be noted that the scalp plaques are notoriously difficult to treat, as they are resistant to systemic therapy; in addition, hair can hinder the application of topical medications and protect the skin from the beneficial effects of ultraviolet (UV) radiation.
Topical treatments
The treatment of psoriasis of the scalp may include the application of products both over the counter (such as a medicated shampoo), and on prescription (such as steroids for topical use).
Depending on the case, the doctor may advise:
- A suspension of 3-5% salicylic acid (keratolytic agent) in mineral oil (such as coal tar), to be applied to the scalp in the evening, before sleeping, then wearing a shower cap (to enhance its penetration and avoid shedding) and rinsing the next morning.
- During the day, corticosteroids can be indicated on the scalp to reduce inflammation or non-steroidal products (eg calcipotriol and other vitamin D derivatives) to slow down the proliferation of keratinocytes. These treatments are continued until the desired clinical response is reached.
- Phototherapy is particularly effective for chronic plaque psoriasis, but it is difficult to apply to the scalp.
- Resistant skin or scalp plaques may respond to local superficial intra-lesion injection of a suspension of triamcinolone acetonide, diluted with physiological solution at 2.5 or 5 mg / ml, depending on the size and severity of the lesion. Infiltrations can lead to generally reversible local atrophy.
- Even bathing in the sea (thalassotherapy) and in sulphurous thermal waters can be useful for treating scalp psoriasis.
Systemic treatments
Systemic drugs may be indicated for some patients with severe scalp psoriasis, refractory to topical treatments. The active ingredients used include: methotrexate, retinoids, cyclosporine or biological drugs.
Scalp hygiene
As for hair care, special attention should be paid to washing the scalp. During cleansing of the hair, the gestures must be very delicate, trying not to scratch the plates.
Then, those suffering from psoriasis on the scalp should not resort to a shampoo formulated with aggressive surfactants and degreasers, but should choose specific products for scalp psoriasis. These detergents, in addition to the antipsoriatic active ingredients, should contain selected ingredients so as not to produce irritation and dryness.
For most patients with psoriasis of the scalp, the medicated products based on coal tar available in pharmacies are suitable, while those based on ketoconazole, cyclopirox and zinc pyrithione can have variable effects.
If using a hair dryer to dry the hair, it is advisable to keep it at least 30 cm away from the head, using a jet of fresh air or a low temperature. When you brush or comb your scalp, instead, a brush with soft and natural bristles can be used, while rigid plastic instruments and rollers should be avoided.
Considering, then, that stress contributes to the manifestations associated with psoriasis of the scalp, it can be useful to practice regular physical activity to release negative tensions and improve nutrition, favoring fruit and vegetables.
