Follicular porokeratosis: distinct clinical entity or histologic variant?

Various clinical subtypes of porokeratosis, clinically characterized by annular plaques with a normal or atrophic center and a distinctive keratotic ridge, are described based on the age of onset, size, number and distribution of the lesions. Follicular involvement, identified by follicular localization of cornoid lamellae, is uncommon and has only been reported in association with other subtypes such as disseminated superficial actinic porokeratosis and porokeratosis of Mibelli. We present a case of follicular porokeratosis in a 40-year-old male who presented initially with scaly red "papules" in a follicular distribution on the upper extremity. Microscopic examination of a punch biopsy specimen revealed parakeratosis confined to the follicle and mild interface change. A repeat biopsy performed in 2008 revealed identical histologic features. In terms of etiopathogenesis, a clone of cells at the base of the follicle demonstrating abnormal keratinization is not a novel concept and has been demonstrated in other porokeratotic dermatoses. However, the presence of lesions that are solely follicular based, in terms of clinical presentation and histologic findings, and static over a 3-year period favors the concept that follicular porokeratosis is a distinct clinical entity and not merely a histologic variant of the porokeratotic dermatoses described in the literature thus far.     

Genital porokeratosis of Mibelli.

Porokeratosis of Mibelli is a disorder of epidermal proliferation in which many different clinical forms can be distinguished. Two male patients with a localized type of porokeratosis limited to the genitalia are reported. Later in life they developed an annular skin lesion with peripheral keratotic ridge. The histological examination of a biopsy specimen showed the characteristic features of porokeratosis. There was no family history of similar skin disorders and the patients were not on any drugs. Genital porokeratosis is probably underdiagnosed and we believe that these patients should be followed up on account of the precancerous potential of this disease.     

Coexistence of congenital linear porokeratosis and disseminated superficial porokeratosis

The coexistence of two or more forms of porokeratosis in a single individual is rarely reported. We report here on a patient exhibiting the coexistence of congenital linear porokeratosis and disseminated superficial porokeratosis. To our knowledge, this entity has been previously reported only once.     

Porokeratosis of Mibelli following bone marrow transplantation

BACKGROUND: Porokeratosis is a rare disorder of keratinization with both autosomal dominant and acquired forms. Immunosuppression has been associated with the development of porokeratosis in numerous case reports and series. To our knowledge, however, only five cases of porokeratosis have been reported following bone marrow transplantation. RESULTS: We report five cases of porokeratosis of Mibelli following bone marrow transplantation. The diagnosis of porokeratosis was made between 1 and 13 years post-transplantation. The underlying malignancy in four of the five cases was leukemia, while the fifth patient had non-Hodgkin's lymphoma. Porokeratosis developed during remission in the four leukemia patients, whereas, in the fifth patient, it occurred during a relapse of lymphoma. CONCLUSIONS: Porokeratosis may develop following bone marrow transplantation. Our five cases double the number reported in the medical literature, and the incidence of porokeratosis following bone marrow transplantation may be significantly higher than previously recognized. As cutaneous carcinomas have been reported in association with porokeratosis, careful surveillance for porokeratosis in bone marrow transplant recipients is warranted.     

伴炎症反应的汗孔角化病三例

汗管角化症是一种少见的慢性角化性皮肤病,以中央轻度萎缩边缘堤状角质嵴围绕的皮损为特征。组织病理学特征为角样板层。本病一般无临床症状,但伴明显瘙痒的汗孔角化症已经有文献报告,并被命名为“发疹性瘙痒性丘疹型汗管角化症”或“处于炎症反应期的DSP”。笔者近期诊断三例这样的病患并推荐使用“发疹性瘙痒性丘疹型汗管角化症”来命名这一特殊类型的汗孔角化症。     

Linear porokeratosis

Linear porokeratosis is a rare variant. It can be present at birth or can develop in adult life. Lesions of linear porokeratosis are grouped and linearly arranged along the lines of Blaschko. On the extremities it affects the distal portion more than the proximal areas. On the trunk these can be zosteriform in distribution. Lesions of linear porokeratosis probably result from an abnormal clone of epidermal precursors. A 20 year old male presented with annular plaques in linear pattern following the lines of Blaschko over the left upper limb extending up to the axilla present since childhood. The lesions had atrophic centre and raised hyperkeratotic borders. The lesions were more proximal than distal. Few scattered lesions were present on left side of trunk. There was no family history of such lesions. Systemic examination of patient was normal. On histopathological examination there was hyperkeratosis and parakeratosis. A coronoid lamella was present. At the base of coronoid lamella thinned out granular layer and necrotic keratinocytes were also seen. In the dermis pigment incontinence and perivascular lymphocytic infiltrate were present. This case is being reported because of its rarity. It is an atypical presentation because the lesions were disposed more over proximal than distal area of upper limb. Linear porokeratosis is associated with an increased risk of malignant transformation.     

Simultaneous development and parallel course of disseminated superficial porokeratosis and ovarian cancer: Coincidental association or true paraneoplastic syndrome?

Disseminated superficial porokeratosis has been described in the setting of immunosuppressive conditions, including organ transplantation, infections, and hematopoietic malignancies. The outbreak of disseminated superficial porokeratosis during the development of solid organ malignancies has been rarely reported in the literature in patients affected by hepatitis C virus-related hepatocellular carcinoma or by cholangiocarcinoma, which suggests a paraneoplastic nature of the cutaneous disease. We report an unusual case of disseminated superficial porokeratosis in a patient affected by ovarian cancer, characterized by simultaneous onset and a parallel course of the two pathologies; there was good clinical response to chemotherapy, accompanied by a successful stop of disseminated superficial porokeratosis progression and gradual clearing of the keratotic lesions.     

Disseminated superficial actinic porokeratosis in a patient undergoing treatment with long-term narrowband ultraviolet B for psoriasis

Disseminated superficial actinic porokeratosis (DSAP) is a subtype of porokeratosis, thought to be clonal disorder of keratinization. Chronic exposure to ultraviolet (UV) light might be an etiological cause of DSAP, of which frequent sites are sun-exposed areas. We report a case of DSAP that occurred on the trunk of a 79-year-old man with psoriasis treated with narrowband ultraviolet B (NB-UVB) for clearing and maintenance therapies. DSAP has been reported to associate with psoralen and ultraviolet A therapy and broadband UVB, but not NB-UVB. This may be the first case of DSAP after repeated exposure to NB-UVB.     

Bowen disease associated with porokeratosis of Mibelli.

A 73-year-old woman developed Bowen precancerous dermatosis in an area of porokeratosis of Mibelli on her leg. This is the fourth reported case of Bowen disease arising from porokeratosis of Mibelli. The recent literature indicates that porokeratosis of Mibelli may be due to an abnormal clone of cells, predisposing affected individuals to development of malignant neoplasms over the involved areas.     

Disseminated superficial "actinic" porokeratosis.

An 81-year-old Finnish female had a 10-month history of a very pruritic eruption. In the clinical examination porokeratosis was suspected and histologically verified with the typical cornoid lamellae. The eruption involved also the unexposed areas of the skin. The patient had always avoided sunshine because it made her feel uncomfortable. The patient's sister, too, had a solitary lesion of porokeratosis. The pathomechanism of DSAP is discussed.     

Eruptive Pruritic Papular Porokeratosis

Three cases of an unusual variant of porokeratosis (Mibelli) were described. Patients with disseminated superficial porokeratosis for some years suddenly developed intensively pruritic erythematous papules. Skin biopsies revealed that these papules contained cornoid lamellae on their tops. Pruritic papules subsided in several months, leaving slightly hyperkeratotic brown annular lesions which were shown to contain typical cornoid lamellae histopathologically. This type of porokeratosis has not been reported in the literature.     

Disseminated giant porokeratosis and porokeratosis of Mibelli in Bankura and Bardhaman districts,West Bengal,India

Porokeratosis of Mibelli (PM) is a rare genodermatosis. It is caused by proliferation of abnormal clones of epidermal cells in response to several stimuli, the most important of which is sunlight. Giant porokeratosis is thought to be a variant of PM. We report two cases of disseminated PM and one case of disseminated giant porokeratosis from the Bankura and Bardhaman districts of West Bengal in India; presenting to a single observer in the summer of 2012. Interestingly we have noted that the majority of cases of porokeratosis in India have been reported from West Bengal. Few patients with a single lesion of giant porokeratosis have been reported in world literature. As far as we know, this is the first case report of disseminated giant porokeratosis in world literature.     

五个汗孔角化病家系的临床和遗传特点

目的 调查5个3种类型汗孔角化病家系的临床和遗传资料,进而分析3种类型汗孔角化病的临床表现和遗传特点。方法 当5个家系先证者的临床诊断明确后(主要诊断依据是特征性皮损和组织病理),现场调查家系资料,对每个家系的家庭成员进行相关临床检查和遗传调查。这5个家系包括3个播散性浅表光线性汗孔角化病(DSAP,共266人,其中患者100例)家系,1个散发性跖汗孔角化病及播散性汗孔角化病(PPPD,共90人,其中患者26例)家系和1个经典斑块型(PM,共34人,其中患者17例)家系。结果 5个家系都为常染色体显性遗传,都具有以边缘呈堤状隆起、中央萎缩的典型皮损,有角化不全细胞柱的病理变化。可分为3种亚型,每一类型各有自身特色。DSAP型是汗孔角化病的一种常见类型,疾病初发年龄较其他类型早(一般8-20岁),初发皮损在颜面部。PPPD型初发年龄为14-20岁,初发皮损为掌跖部或面部,初发皮损为掌跖部者病情较重,初发皮损为面部者病情较轻。PM型的初发年龄较迟,为20-30岁,初发皮损为前臂、手背、耳际和前额等非特定部位。PPPD型家系和PM型家系都有汗孔角化病不同类型的共存现象。结论 汗孔角化病是一种具有不同表现度的常染色体显性遗传病,具有多种临床类型和不同的遗传基础,不同临床类型间既存在一致性也存在差异性,而且不同临床类     

掌跖及泛发性汗孔角化症一家系报道

报告我国首例掌跖及泛发性汗孔角化症一家系调查。先证者10岁时右手中指掌尺侧出现一油菜籽大小的圆形角化性丘疹，继后发现面部出现相似丘疹，且皮损逐渐扩大并泛发全身；组织病理检查可见角化不全柱，符合汗孔角化症；家系调查为5代共90人，结果患病26例，其中男性17例，女性9例，符合常染色体显性遗传特点。诊断为显性遗传性掌跖及泛发性汗孔角化症。对该病的临床特征、组织病理、遗传方式及鉴别诊断等进行了讨论。     

POROKERATOSIS OF MIBELLI AND HIV-INFECTION

Background. The exacerbation of porokeratosis of Mibelli associated with inmunosuppression has been well documented. Materials and Methods. We describe the clinical and histologic data of three cases of HIV-infected patients, who developed porokeratosis following HIV-contact. Results. The three reported patients were found to have the clinical and histologic features of porokeratosis of Mibelli. Either the exacerbation or development of the disease followed HIV infection. Conclusion. Although porokeratosis is not a disease indicative of AIDS, its flare-up or its presence in HIV-infected patients may serve as a marker of inmunodeficiency.     

Porokeratosis confined to the genital area: a report of three cases

Genital involvement in porokeratosis (PK) is a rare occurrence even in disseminated forms. We encountered three patients who had porokeratosis affecting only the genital area. Two of them were male with involvement of the penis and scrotum and only the scrotum respectively. The lady with vulvar involvement is a hitherto unreported instance of porokeratosis confined to female genitalia. None of the cases were very easy to diagnose clinically but biopsies proved confirmatory. The male patients were advised light electrocautery under local anesthesia while the female patient underwent surgical excision. No malignant change has been reported in them till date.     

Linear porokeratosis with underlying bony abnormalities

A 58-year-old woman with linear porokeratosis involving the right hand and arm had distal digital narrowing and nail dystrophy with radiographic changes. Whereas isolated cases of bone resorption and flexion deformities with porokeratosis of Mibelli are known to occur, to our knowledge, bony abnormalities in association with linear porokeratosis have not been reported.     

Disseminated superficial actinic porokeratosis with both typical and prurigo nodularis-like lesions

We report a 50-year-old Korean patient who developed a disseminated superficial actinic porokeratosis (DSAP) with two types of lesions. One was a typical DSAP lesion clinically and histopathologically. The other was clinically similar to prurigo nodularis, but histologic examination showed the findings of porokeratosis such as cornoid lamellae and loss of the granular layer in addition to those of chronic lichenified dermatitis, so it could be described as prurigo nodularis-like porokeratosis. The nodular lesions seemed to develop on preexisting typical lesions of DSAP mainly during the summer by the aggravation of pruritic symptoms and scratching associated with sun exposure. Although we could not find any published reports describing lesions like those of our case, we think that such prurigo nodularis-like porokeratosis can develop in patients with DSAP in some situations involving pruritus and scratching.     

Eruptive pruritic papular porokeratosis: a pruritic variant of porokeratosis

Porokeratosis is a chronic skin disorder characterized clinically by the presence of crater-like patches with an elevated thick keratotic border and central atrophy. Histology reveals cornoid lamellae. While porokeratosis is practically asymptomatic, a pruritic variant has been reported. We recently encountered an 82-year-old man with pruritic porokeratosis. He presented with erythematous papules and intensively itchy patches on his lower limbs that had been present for 6 months. Histopathological examination revealed the characteristic cornoid lamellae. We describe this case in detail and provide a review of the published work.     

表现为发疹性瘙痒性丘疹的汗孔角化病

报告1例表现为发疹性瘙痒性丘疹的汗孔角化病.患者男,50岁.臀部丘疹伴剧烈瘙痒7年,逐渐融合成斑块,丘疹突然增多并累及双下肢1年.皮损组织病理检查符合汗孔角化病.给予角质剥脱剂外用及阿维A口服治疗4周,皮损暂无明显改善.