DermNet NZ was founded 23 years ago by a group of Dermatologists from New Zealand. It has become a world-renowned resource of skin disease information.

Climate change is a lasting alteration in patterns of weather caused by factors such as oceanic circulation, variations in solar...

Rickettsiae are small, obligate intracellular, Gram-negative bacteria that spend part of their life cycle in an arthropod host (eg, a tick,...

Guselkumab is a biological treatment indicated for moderate-to-severe psoriasis.The US Food and Drug Administration (FDA) has approved guselkumab (Tremfya™, Janssen...

Prader–Willi syndrome is the most common genetic cause of obesity. It was first described in 1887 by John Langdon Down,...

The classical tests for immediate type I hypersensitivity (allergy) are specific immunoglobulin E (IgE) antibody levels, such as the radioallergosorbent test...

Prepubertal acne has been classified into the following age groups by a panel convened by the American Acne and Rosacea...

Cutaneous melanoma is generally first suspected during a skin check and the diagnosis is confirmed by a positive skin...

Hypnosis, or hypnotherapy, induces someone to enter into a 'trance state' using deep breathing and relaxation, meditation and guided imagery. It mandates...

Melanocytes make two forms of melanin in the skin, hair, and eyes.

Lichen simplex of the scrotum is a pruritic form of dermatitis in which excessive scratching or rubbing leads to lichenification.

In March 2018, tildrakizumab (Ilumya™; Sun Pharma India) received US Food and Drug Administration (FDA) approval for the treatment of...

Lichen simplex of the vulva is a pruritic form of dermatitis in which excessive scratching or rubbing leads to lichenification.

A convolutional neural network (CNN) is a type of deep artificial neural network used in image processing.

Linea nigra is a physiological form of hyperpigmentation commonly seen in the first trimester of pregnancy [1–3].

Nipple eczema is a localised dermatitis involving the nipple and areola, and is characterised by erythema and scaling.

Intravascular lymphoma is a rare subtype of large B-cell lymphoma in which lymphoma cells proliferate within the lumen of small...

Cellulitis is an acute bacterial infection of the dermis and subcutaneous tissues of the skin.

Hidradenitis suppurativa is a debilitating and distressing chronic inflammatory skin disease affecting about one in every 150 Australians.

Intralymphatic histiocytosis is a rare benign chronic skin condition most commonly associated with rheumatoid arthritis, orthopaedic metal implants, or cancer...

Tranexamic acid is an anti-fibrinolytic agent, and is commonly used for heavy menstrual bleeding.

A picosecond laser is a laser device that uses very short pulse durations to target endogenous pigmentation and exogenous ink...

Klippel-Trénaunay syndrome (KTS) is a rare congenital vascular bone syndrome that is characterised by a triad of symptoms and...

Blue toe syndrome, also known as occlusive vasculopathy, is a form of acute digital ischaemia in which one or more...

Primary dermal melanoma, also known as solitary dermal melanoma, represents melanoma confined to the dermis without an epidermal (junctional)...

Cemiplimab is a monoclonal antibody used for patients with advanced cutaneous squamous cell carcinoma (SCC).

Clinical trials have demonstrated that cemiplimab is effective in patients with advanced cutaneous squamous cell carcinoma (SCC).

Giant cell arteritis is a form of vasculitis that most commonly affects the arteries of the scalp and head when...

Keratolytic winter erythema is a rare inherited skin disorder characterised by recurrent palmoplantar erythema and peeling that is often worse...

Hypogonadism describes the inadequate function of the gonads with impaired production of germ cells and sex hormones. What is hypogonadism in males?Hypogonadism...

Periorificial dermatitis in children typically presents as multiple small papules around the mouth, nose and eyes.While the name is suggestive...

Chronic inducible urticaria is chronic urticaria that has an attributable cause or trigger and is classified according to the stimulus...

Urticaria is a condition characterised by the presence of hives/weals (also spelt wheals) and/or angioedema [1,2].

IntroductionMycosis fungoides is the most common form of cutaneous T cell lymphoma. It is characterised by infiltrates of lymphocytes. It has an...

Lymphangioma circumscriptum presents on the skin surface as grapelike groups of thin-walled, translucent, lymph-filled vesicles, often compared with frog...

Pseudocarcinomatous hyperplasia can occasionally be observed in biopsies of CD30-positive lymphoproliferative disorders.

Combined trichoepithelioma and cellular blue naevus is a rare lesion that may mimic melanoma clinically.Histology of combined trichoepithelioma and cellular blue...

Glomangiomas (also called glomuvenous malformation) differ clinically from glomus tumors in that they occur in childhood and adolescence, are usually asymptomatic,...

Panfolliculoma is a benign neoplasm of follicular differentiation that was initially described by Ackerman et al.

Intralymphatic histiocytosis manifests as quite non-descript erythematous patches or plaques. Autoimmune disease, malignancy, joint replacements, and rosacea appear to be aetiologic...

Elastofibroma usually presents on the back (usually in the subscapular region) as a poorly defined mass or pseudotumour.

Subungual melanoma is cancer that arises from a malignant proliferation of melanocytes in the nail matrix.

Human gnathostomiasis presents as larva migrans profundus, and is caused by ingesting gnathostoma larvae.

Clear cell fibrous papule is a rare variant of fibrous papule that has a clinical presentation identical to conventional fibrous...

Synovial sarcoma is usually an aggressive deep seated mass presenting around large joints (80% in knee and ankle) in young...

Chickenpox is caused by primary infection with the varicella-zoster virus, of the Herpesviridae family.

Mesothelioma is a malignant tumour arises from mesothelial lining of pleura, peritoneum, pericardium and tunica vaginalis — pleural mesothelioma is the...

Cutaneous larva migrans is a parasitic skin infection caused by helminth larvae that usually infest cats, dogs and other...

Epithelioid hemangioma is a benign vascular lesion of the skin or deeper structures (bone).

Neurocristic hamartoma presents as a slowly enlarging multinodular variably pigmented plaque. It most commonly presents in the head and neck region but...

Neurofollicular hamartoma presents as a smooth flesh-coloured papule on the face.Histology of neurofollicular hamartomaIn neurofollicular hamartoma, the histopathology shows a...

Pseudoepitheliomatous keratotic and micaceous balanitis is a coronal balanitis that gradually takes on a silvery white appearance due to mica-like...

Eosinophilic granulomatosis with polyangiitis is also known as Churg–Strauss syndrome and allergic granulomatosis.

Angiokeratoma presents as a blood-filled papule which may bleed following trauma.

Angiomatoid fibrous histiocytoma is an uncommon variant of fibrohistiocytic tumor with intermediate malignant potential (metastases are rare but do occur).

New therapies targeting BRAF and MEK have emerged as the key component for the treatment of BRAF-mutant metastatic melanoma.

Splenosis may present in the skin following splenic trauma and subsequent spread of benign splenic tissue into surrounding structures.

Glomeruloid haemangioma is a rare benign cutaneous vascular proliferation that typically arises in patients with a history of POEMS...

Sclerosing lipogranuloma usually presents as a painless or slightly tender, indurated mass on the penis, scrotum, spermatic cord and...

Lichenoid drug reactions are induced by a medication or another exogenous source which can mimic other lichenoid dermatoses clinically and...

Systemic amyloidosis caused by the buildup of amyloid in various organs.

Myiasis is infestation by the larvae of fly species within the arthropod order Diptera (the adult flies are two-winged).

Verrucous haemangioma presents as blue-red, vascular papules, plaques or nodules, which later become warty in appearance.

Juvenile xanthogranuloma usually presents in younger individuals as smooth pink or yellow nodules.

Eruptive xanthoma presents as crops of pink papules which are often pruritic.



Guidelines for authors

Are you interested in writing for us? DermNet New Zealand is always looking for potential authors to write on new topics. Potential authors interested in writing a new page are generally asked to write a topic page on either a disease or condition, or a treatment, product or procedure.

Read more