Topics covered in this Tutorial
Acrokeratosis verruciformis
Plugging in the skin
Fox Fordyce disease
Perforating disorders
Follicular papules
Plaques of micropapules
Subcutaneous Phycomycosis
Jessners lymphocytic infiltrate
White plaques in the mouth
Bald areas in the scalp
Keratosis Pilaris atrophicans
Acrokeratosis verruciformis
This is an autosomal dominant disease, which particularly affects the hands, feet, knees, elbows and forearms. There are often palmar pits and friction blisters. The nails may be thickened and white. There are also hypopigmented spots.
View Dermnet on Darier's disease
The image below is of acrokeratosis
Plugging
Plugging can be due to a comedone which can be both superficial and deep or a milium, which is seen in normal skin. The follicular keratoses are a primary phenomenon of plugging. Plugging can be a secondary phenomenon in conditions such as lupus erythematosus of the discoid variant when it involves hair bearing areas and conditions such as lichen plano pilaris and lichen sclerosis.
The skin colour is slightly pigmented with dome shaped papules. They come on at puberty particularly in females. It can affect the breasts and inner genital areas with pruritus, it is persistent and it is particularly a risk in pregnancy.
Lichen spinulosus is a cutaneous reaction pattern. Lichen scrofulosorum is an id reaction associated with tuberculosis. Plugging can be simulated by miliary papular syphillis and also drug reactions.
![]() |
| Lichen spinulosus |
![]() |
| Lichen scrofulosorum |
Reactive Perforating Collagenosis
Here you may have a dome shaped 5mm papule with a central keratin core. Particularly occurs on the hands after trauma. It may regress with temporary hypopigmentation and you can see lesions at different stages. It exhibits the Koebner phenomenon and it occurs over a period of years. See cases in GSA
Elastosis Perforans Serpiginosa
There are various diseases that it can occur with. It is one of the elastic tissue diseases. It presents with annular or linear lesions particularly on the neck and cheeks or the antecubital fossae or the upper thighs.
The image below is of Elastosis perforans serpiginosa
Follicular Papules
Consider the keratosis pilaris group. Then the id group, particularly lichen scrofulosorum and lichen spinulosus. The perforating group particularly perforating collagenosis, porokeratosis, elastosis perforans serpiginosa and perforating granuloma annulare and then there is a nutritional group with Vitamin D or Vitamin C deficiency. Follicular papules are also presenting features of pityriasis rubra pilaris and Darier’s disease
The image below shows the follicular papules of early Pityriasis rubra pilaris
Plaques of Micropapules
Consider sarcoidosis, granuloma annulare, lichen planus, lichen scrofulosorum, lichen nitidus, lichen plano pilaris, eczema, follicular mucinosis, lichen myxedematosus, lichen amyloid, acrokeratosis verruciformis, epidermodysplasia verruciformis.
Follicular Accentuation
If you get infiltrates around follicles consider either mucin, sarcoid or xanthomata.
Annular Serpiginous Lesions
Consider Sign Dip and the four Ps and L. Consider pemphigus, porokeratosis, the pustuloses, the perforating diseases and lichen sclerosis et atrophicus.
The image below is lichen nitidus
Subcutaneous Phycomycosis
This is granuloma due to fungi in fatty tissue. It is disc shaped and can have a firm rubber like consistency. The overlying skin may be tense, oedematous, desquamating. It can be hyperpigmented or normal and the regional nodes are not enlarged. The differential diagnosis is lymphatic oedema but this does not have an edge. Subcutaneous malignant lymphoma, which grows rapidly and also induration around an injection site are other possibilities. Particularly nurses injecting Pentazocine. Acanthamoeba infection is as rare cause of firm facial plaques.
![]() |
| Rare example of a firm facial plaque due to acanthamoeba infection |
See web site associated with this image
Jessners Lymphocytic Infiltrate
This is often pink to red brown with a central clearing tendency particularly on the face and neck and it is relapsing. Many people consider it a variant of lupus erythematosus.
Lymphocytoma Cutis This is a collection of benign normal looking lymphocytes in the skin. It particularly follows insect bite reactions. Classic sites for it though are the scrotum, nipples and the earlobes. It can create alopecia.
Granuloma Faciale Occurs particularly on the face. There are prominent follicular openings, it is painless and it is soft. Usually red or violaceous in colour. Often seen on the nose.
The image below is of Jessners Lymphocytic infiltrate
White Plaques in the Mouth
Dyskeratosis congenita and pachyonychia congenita both occur on the tongue. In contrast white sponge nevus does not occur on the tongue but on the gingival surfaces or buccal surfaces of the cheek and can also be seen on the anus and the vagina.
There is no lymphadenopathy but there is toxaemia. Lymphangitis is unusual. You get haemorrhage and necrosis and sometimes a gelatinous oedema. The differential diagnosis can be ecthyma due to pseudomonas, a staph infection, accidental vaccinia, cowpox, cat scratch disease, North American blastomycosis and sporotrichosis.
Bald Areas in the Scalp
Consider a variety of diseases as to whether this is a scarring alopecia or a non-scarring. There are the simple conditions such as fungal infections, alopecia areata and diseases such as lupus or lichen plano pilaris. Three others to consider include pseudopelade, folliculitis decalvans and the Graham Little syndrome. Pseudopelade is a specific reaction pattern on its own. There are three variants, the localised, the diffuse and the type in Negro women. It occurs particularly on the vertex with baldness and slow progression. A biopsy shows inflammation in the upper two-thirds of the follicle. Folliculitis decalvans is a slow balding condition particularly in the temple area in males. It is unilateral but can be bilateral. There are brown or red lupoid like papules or pustules in the advancing edge. All hair areas can be affected. The differential diagnosis is favus, tinea and follicular mucinosis. The Graham Little Syndrome is a variant of lichen plano pilaris particularly in women. Frontal fibrosing alopecia is seen in post menopausal women with slow receding of the frontal hair line with perifollicular redness and scale.
The image below is listed as pseudopelade
There are several variants of this condition. Keratosis pilaris atrophicans faceii is usually confined to the eyebrows. This is sometimes known as Ulerythema oopherogenes. The second type is atrophoderma vermiculatum. This affects the cheeks and it is an autosomal dominant disorder. The third type is keratosis pilaris decalvans, which is very extensive keratosis pilaris with a scarring alopecia of the scalp and other regions. It is probably an autosomal recessive whereas ordinary keratosis pilaris is autosomal dominant. Regarding atrophoderma vermiculatum it occurs between the ages of five and 12 on the preauricular or cheek areas. There is erythema and pinhead plugs and when the plugs fall out there is a reticulate atrophy with variable milia.
![]() |
| Keratosis pilaris atrophicans |













