Five Most Common Types of Psoriasis

1. Plaque Psoriasis

Plaque Psoriasis is the most common subtype, representing about 90% of all cases. It results in symmetrical distribution of plaques on the scalp, knees, elbows, and sometimes above the buttocks. It tends to worsen during the winter months.

2. Guttate Psoriasis

Guttate Psoriasis is characterized by small, dot-like lesions on the trunk. This condition can be triggered by factors such as strep throat. You may find more plaques due to koebnerization, where skin lesions appear in areas of trauma or injury. This type of psoriasis can be particularly distressing due to its sudden onset and widespread nature.

Guttate psoriasis outbreak showing numerous red, scaly spots

Meier K, Schloegl A, Poddubnyy D, Ghoreschi K. Skin manifestations in spondyloarthritis. Ther Adv Musculoskelet Dis. 2020 Dec 8;12:1759720X20975915. doi: 10.1177/1759720X20975915. PMID: 33343725; PMCID: PMC7727049.

Haulrig MB, Zachariae C, Skov L. Off-Label Treatments for Pediatric Psoriasis: Lessons for the Clinic. Psoriasis (Auckl). 2021 Feb 11;11:1-20. doi: 10.2147/PTT.S268462. PMID: 33604269; PMCID: PMC7886293.

Huang YW, Tsai TF. Exacerbation of Psoriasis Following COVID-19 Vaccination: Report From a Single Center. Front Med (Lausanne). 2021 Dec 23;8:812010. doi: 10.3389/fmed.2021.812010. PMID: 35004790; PMCID: PMC8733241.

3. Inverse Psoriasis

Inverse Psoriasis occurs in skin folds (armpits, under the breasts, in the groin). There is no scale and a “shiny” appearance. The condition can be particularly uncomfortable due to the friction and moisture present in these areas, which can exacerbate symptoms and lead to irritation.

Inverse psoriasis with red, smooth lesions on armpit skin

Inverse psoriasis with red, smooth lesions under breasts

4. Scalp Psoriasis

Scalp Psoriasis occurs in ~50% of psoriasis patients and can extend onto forehead, neck, and behind the ears. This form of psoriasis can range from mild to severe, and in some cases, it can cause hair loss due to the constant scratching and inflammation. Managing scalp psoriasis can be particularly challenging due to the presence of hair, which can make applying topical treatments more difficult.

Scalp psoriasis on forehead with red patches and silvery scales

Red, scaly psoriasis patches behind ears and on scalp

Psoriasis affecting back of scalp with inflamed, scaly skin

5. Nail Psoriasis

Nail Psoriasis is a common manifestation of psoriasis, affecting the fingernails and toenails and presenting with a range of symptoms. These can include pitting, discoloration, thickening, and separation of the nail from the nail bed (onycholysis). Additionally, patients may notice irregular nail growth and the formation of small, reddish spots under the nails (oil drop or salmon patch). Nail psoriasis can be particularly distressing due to its visibility and potential impact on daily activities. Treatment is difficult, but options include topical medications, injections, and systemic treatments.

Nail Pitting

Little pits in the nail

Onycholysis

End of nail lifting up

Pitting + Onycholysis

Nail Crumbling

Onycholysis Image: Nieradko-Iwanicka B. Nail psoriasis - what a rheumatologist should know about. Reumatologia. 2017;55(1):44-47. doi: 10.5114/reum.2017.66687. Epub 2017 Mar 22. PMID: 28386142; PMCID: PMC5380772.

Nail Crumbling Image: Piraccini BM, Starace M. Optimal management of nail disease in patients with psoriasis. Psoriasis (Auckl). 2015 Jan 9;5:25-33. doi: 10.2147/PTT.S55338. PMID: 29387579; PMCID: PMC5683109.