The aim of this review was to find out how well different non-antistreptococcal treatments (i.e. drugs not aimed at eradicating streptococcal infection) work for treating acute guttate psoriasis or an acute guttate flare of chronic psoriasis in adults and children, and how safe they are when compared against placebo (an identical but inactive treatment) or another treatment. This was important because there is a lack of information and evidence about the best way to treat guttate psoriasis. We collected and analysed all relevant studies to answer this question and found one study.
Psoriasis is a chronic skin disease characterised by patches of red, flaky skin covered with scales (known as plaques). Approximately 2% of people have psoriasis. Guttate psoriasis is a type of psoriasis that is characterised by smaller lesions and is more common in children and young people. Treatments for guttate psoriasis aim to clear the skin of lesions for as long as possible, and include topical (applied to the skin) or oral (taken by mouth) medicines; phototherapy (i.e. ultraviolet light therapy); and biological medicines (whereby a living organism creates the active substance). It is not known which of these treatments work best at clearing lesions in guttate psoriasis and whether they are safe.
We found one relevant study that compared the effects of giving injections into the vein of two different lipid (fat) emulsions twice daily for 10 days: one emulsion (two or more liquids that are often unmixable) was derived from fish oil, and the other was derived from soya oil. Participants were followed for a total of 40 days. The study was conducted in Germany in 21 adults (18 men and 3 women) aged 21 to 65 years, with a mean of involved skin surface of 25%, who were in hospital with acute guttate psoriasis. The study was funded by the company that produces the oil emulsions.
Treatments for which we found no evidence include phototherapy and topical, oral, and biological medicines. The only study identified did not measure our two primary outcomes: percentage of people treated whose skin became clear (or almost clear) of lesions; and the side effects, or harms, of the treatments.
Most of our secondary outcomes were also not measured, including worsening of guttate psoriasis or recurrence within a period of six months after the treatment has finished; and percentage of participants achieving a Psoriasis Area Severity Index 75 or Physician's Global Assessment of 1 or 2. The included study did not report measuring any harms of the treatments; however, the study authors did report rare skin irritation at site of injection, but did not provide the number of affected participants.
The study participants rated some outcomes themselves, including the appearance of the skin lesions, the effects on their daily life, itching, burning, and pain. After 10 days of treatment, study participants who received the fish oil-derived lipid emulsion (75% of people in this group) rated greater improvements than those receiving the soya oil-derived lipid emulsion (18% of people in this group). However, these results are uncertain as they are based on very low-quality evidence.
The evidence is current to June 2018.
Quality of the evidence
We rated the quality of the available evidence as very low.
We considered that the study may be at risk of bias due to limitations in its design, and only a small number of people were included in the study. In addition, the study only enrolled adults, although guttate psoriasis is more common in children.
There is no evidence regarding topical and systemic drugs, biotherapy, or phototherapy in guttate psoriasis (we did not consider drugs that aimed to eradicate streptococcal infection because these are assessed in another Cochrane Review). We are uncertain of the effect of intravenously administered lipid emulsion on guttate psoriasis because the quality of the evidence is very low, due to risk of bias (unclear risk of bias for all domains), indirectness (the trial only included adults, and the follow-up from baseline was only 10 days), and imprecision (small number of participants).
This review highlights the need for trials assessing the efficacy and safety of phototherapy and topical and systemic drugs for guttate psoriasis. There is also a need for studies that clearly distinguish the specific population with guttate psoriasis from the larger group of people with chronic plaque psoriasis, and children and young adults should be assessed as a distinct group.
Guttate psoriasis displays distinctive epidemiological and clinical features, making it a separate entity within the heterogeneous group of cutaneous psoriasis types. It is associated with genetic, immune, and environmental factors (such as stress and infections) and usually arises in younger age groups (including children, teenagers, and young adults). There is currently no cure for psoriasis, but various treatments can help to relieve the symptoms and signs. The objectives of treatment when managing an acute flare of guttate psoriasis are to reduce time to clearance and induction of long-term remission after resolution. This is an update of a Cochrane Review first published in 2000; since then, new treatments have expanded the therapeutic spectrum of systemic treatments used for psoriasis.
To assess the effects of non-antistreptococcal interventions for acute guttate psoriasis or an acute guttate flare of chronic psoriasis.
We searched the following databases up to June 2018: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We searched five trials registers and checked the reference lists of included studies for further references to relevant randomised controlled trials. We checked the proceedings of key dermatology conferences from 2004 to 2018, and also searched for trials in the US Food and Drug Administration (FDA) database for drug registration.
All randomised controlled trials assessing the effects of treatments for acute guttate psoriasis or an acute guttate flare of chronic psoriasis clinically diagnosed in children and adults. This included all topical and systemic drugs, biological therapy, phototherapy (all forms: topical and systemic), and complementary and alternative therapies. We compared these treatments against placebo or against another treatment. We did not include studies on drugs that aim to eradicate streptococcal infection. We did not include studies when separate results for guttate psoriasis participants were not available.
Two review authors independently assessed study eligibility and methodological quality and extracted data. We used standard methodological procedures expected by Cochrane. Our primary outcomes were 'percentage of participants clear or almost clear (i.e. obtaining Psoriasis Area Severity Index (PASI) 100/90 and/or Physician's Global Assessment (PGA) of 0 or 1)' and 'percentage of participants with adverse effects and severe adverse effects'. Our secondary outcomes were 'number of relapses of guttate psoriasis or flares within a period of six months after the treatment has finished', 'percentage of participants achieving a PASI 75 or PGA of 1 or 2', and 'improvement in participant satisfaction measures and quality of life assessment measures'. We used GRADE to assess the quality of the evidence for each outcome.
This review included only one trial (21 participants), which compared fish oil-derived (n-3) fatty acid-based lipid emulsion (50 mL per infusion (1.05 g eicosapentaenoic and 10.5 g docosahexaenoic acid)) (10 participants) to soya oil-derived (n-6) fatty acid-based lipid emulsion (50 mL per infusion (1.05 g eicosapentaenoic and 10.5 g docosahexaenoic acid)) (11 participants) administered intravenously twice daily for 10 days, with a total follow-up of 40 days. The study was conducted in a single centre in Germany in 18 men and three women, aged between 21 and 65 years, who were in hospital with acute guttate psoriasis and had mean total body surface involvement of 25.7% ± 20.4% (range 10 to 90). The study was funded by a company that produces the oil emulsions. We found no other evidence regarding non-antistreptococcal interventions used in clinical practice for guttate psoriasis, such as topical treatments (corticosteroids, vitamin D₃ analogues), systemic drugs, biological therapy, and phototherapy.
The primary outcomes of the review were not measured, and only one of our secondary outcomes was measured: improvement in participant satisfaction measures and quality of life assessment measures. However, the study authors did report that there was rare skin irritation at the site of peripheral intravenous route, but the number of affected participants was not provided.
Improvement between baseline and day 10, using a non-validated score assessed by participants themselves daily based on five items (appearance of lesions, impairment of daily life, pruritus, burning, and pain), was greater in the group that received the fish oil-derived (n-3) fatty acid-based lipid emulsion (75%) than in the group receiving the soya oil-derived (n-6) fatty acid-based lipid emulsion (18%) (one trial, 21 participants). However, these results are uncertain as they are based on very low-quality evidence.