You are in: eMedicine Specialties > Dermatology > PAPULOSQUAMOUS DISEASES Granular ParakeratosisArticle Last Updated: Jan 29, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 10
  Author: Noah S Scheinfeld, MD, JD, FAAD, Assistant Clinical Professor, Department of Dermatology, Columbia University; Consulting Staff, Department of Dermatology, New York Medical College-Metropolitan Hospital; Private Practice Noah S Scheinfeld is a member of the following medical societies: American Academy of Dermatology Editors: Peter Fritsch, MD, Chair, Department of Dermatology and Venereology, University of Innsbruck, Austria; David F Butler, MD, Professor of Dermatology, Texas A&M University College of Medicine; Director, Division of Dermatology, Scott and White Clinic; Director Dermatology Residency Training Program, Scott and White Clinic; Jeffrey J Miller, MD, Associate Professor, Department of Dermatology, Penn State University, Milton S Hershey Medical Center; Joel M Gelfand, MD, MSCE, Medical Director, Clinical Studies Unit, Assistant Professor, Department of Dermatology, Associate Scholar, Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center Author and Editor Disclosure Synonyms and related keywords: axillary granular parakeratosis, intertriginous parakeratosis, AGP, GP INTRODUCTIONSection 2 of 10
  BackgroundGranular parakeratosis, a benign condition, was first described in 1991 as a skin disease manifesting with erythematous hyperpigmented and hyperkeratotic papules and plaques of the cutaneous folds.1 It is sometimes associated with pruritus. Granular parakeratosis has been associated with excessive use of topical preparations, in particular antiperspirants and deodorants; however, it has been found in persons who have not used such agents. It is also associated with an occlusive environment, increased sweating, and, sometimes, local irritation. Some have linked it to obesity. PathophysiologyThe etiology of granular parakeratosis is uncertain, but Metze and Rütten2 defended the hypothesis, first proposed by Northcutt et al,1 that a basic defect exists in the processing of profilaggrin to filaggrin, which maintains the keratohyaline granules in the stratum corneum during cornification. Because granular parakeratosis has been associated with excessive use of topical preparations, an occlusive environment, increased sweating, and, sometimes, local irritation, some suggest that it is an allergic contact or irritant reaction.3 Some patients who have manifested granular parakeratosis have not used topical preparations, and, thus, the causal linkage of granular parakeratosis to topical substances is unclear. The primary cause for this disease remains unknown. See Contact Dermatitis, Allergic and Contact Dermatitis, Irritant for more information on those topics. FrequencyUnited StatesOnly approximately 40 case reports of this condition have been published, but it is likely more common than the number of case reports suggests. Scheinfeld and Mones4 reviewed the diagnoses of 363,343 specimens submitted to the Ackerman Institute of Dermatopathology in InternationalOnly rare case reports are noted, but it is probably not a rare condition. In 2002, Rodriguez5 reported 3 cases in women in Mortality/MorbidityIts only associated symptom is pruritus. RaceNo racial association has been reported. Granular parakeratosis has been reported in blacks and whites. SexMost reported cases of granular parakeratosis have occurred in women. Whether this finding represents a reporting bias or a real association is unclear. AgeGranular parakeratosis has been reported in children,6, 7 but it is mostly reported in women aged 40-50 years.8 CLINICALSection 3 of 10
HistoryPatients present with a 1- to 12-month history of axillary or intertriginous rash. Sometimes, the rash is pruritic; sometimes, it is not.
PhysicalGranular parakeratosis manifests with intertriginous (ie, groin, intermammary or submammary region, and abdominal folds) bilateral or unilateral brown- or red-crusted patches, papules, or plaques. The rash can be confluent or reticulated. Even when patches or plaques are present, discrete papules can also be present. Granular parakeratosis can appear as slightly erythematous and lichenified plaques.
CausesThe cause of granular parakeratosis is uncertain. Although controversial, the following have been implicated as etiologies for granular parakeratosis:
Importantly, because cases have been reported when these factors were not been present, their importance is not clear. In children, excessive washing has been noted in a series of 4 patients.6 Several authors have postulated that in granular parakeratosis, a basic defect exists in the processing of profilaggrin to filaggrin. Filaggrin maintains the keratohyaline granules in the stratum corneum during cornification. DIFFERENTIALSSection 4 of 10
Acanthosis Nigricans Bowen Disease Confluent and Reticulated Papillomatosis Erythrasma Extramammary Paget Disease
|
| Drug Name | Isotretinoin (Accutane) |
|---|---|
| Description | Oral agent that treats serious dermatologic conditions. Isotretinoin is the synthetic 13-cis isomer of the naturally occurring tretinoin (trans-retinoic acid). Both agents are structurally related to vitamin A. Isotretinoin is a second-line treatment because it has frequent adverse effects and because topical medications can effectively treat this condition. |
| Adult Dose | Some have suggested a dose of 0.5-1 mg/kg/d PO until the condition resolves, but, if used, dose should not exceed 20 mg/d |
| Pediatric Dose | Not recommended |
| Contraindications | Documented hypersensitivity; pregnancy |
| Interactions | Toxicity may occur with vitamin A coadministration; pseudotumor cerebri or papilledema may occur when coadministered with tetracyclines; may reduce carbamazepine plasma levels |
| Pregnancy | X - Contraindicated; benefit does not outweigh risk |
| Precautions | May decrease night vision; inflammatory bowel disease may occur; may be associated with development of hepatitis; occasional exaggerated healing response of acne lesions (excessive granulation with crusting) may occur; patients with diabetes may experience problems in controlling blood glucose levels while on isotretinoin; avoid exposure to UV light or sunlight until tolerance achieved; discontinue treatment if rectal bleeding, abdominal pain, or severe diarrhea occur; mood swings or depression may occur; caution if history of depression |
| Drug Name | Tretinoin (Avita, Retin-A, Renova) |
|---|---|
| Description | Inhibits microcomedo formation and eliminates existing lesions. Makes keratinocytes in sebaceous follicles less adherent and easier to remove. Available as 0.025%, 0.05%, and 0.1% creams. Also available as 0.01% and 0.025% gels. Can be a first-line treatment in granular parakeratosis but is irritating and should be used with caution. |
| Adult Dose | Apply topically qd |
| Pediatric Dose | Not established |
| Contraindications | Documented hypersensitivity |
| Interactions | Other skin irritants (eg, astringents, benzoyl peroxide, salicylic acid, resorcinol, topical sulfur, other keratolytics, abrasives, spices, lime) may exacerbate irritation; coadministration with other drugs causing photosensitivity (eg, tetracycline, sulfonamides) may increase risk of sunburn |
| Pregnancy | C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus |
| Precautions | Photosensitivity may occur with excessive sunlight exposure; burning, stinging, peeling, pruritus, or erythema has been reported at site of application; caution with eczema (may cause severe irritation); do not apply to mucous membranes, mouth, and angles of nose |
| Drug Name | Tazarotene (Tazorac) |
|---|---|
| Description | Topical medication approved for psoriasis and acne. Useful in normalizing functioning of epithelial cells. Acts on a genetic level, leading to the transcription of certain retinoic acid genes. Use is off-label. |
| Adult Dose | Apply to rash qd |
| Pediatric Dose | Apply as in adults |
| Contraindications | Documented hypersensitivity; excess irritation; pregnancy |
| Interactions | Do not use concomitantly with dermatologic drugs or cosmetics that have a strong drying effect on skin (eg, salicylic acid, benzoyl peroxide, astringents) |
| Pregnancy | X - Contraindicated; benefit does not outweigh risk |
| Precautions | May cause burning or stinging sensations; discontinue if excessive irritation occurs; rinse thoroughly if contact with eyes, eyelids, or mouth; may cause severe irritation in eczematous skin; photosensitivity may occur |
These agents are essential for normal DNA synthesis and metabolism of proteins, carbohydrates, and fats. They may also work as cofactors used in aerobic cellular respiration.
| Drug Name | Calcipotriene (Dovonex) |
|---|---|
| Description | Topical preparation containing vitamin D-3. Indicated for psoriasis. Seems to normalize maturation of epidermal cells. |
| Adult Dose | Apply to rash bid |
| Pediatric Dose | Apply as in adults |
| Contraindications | Documented hypersensitivity; hypercalcemia; vitamin D toxicity |
| Interactions | None reported |
| Pregnancy | C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus |
| Precautions | Rarely can lead to elevated serum calcium level; discontinue treatment if skin becomes irritated; discontinue if serum calcium level is increased outside reference range |
This agent normalizes skin function.
| Drug Name | Lactic acid (Lac Hydrin, AmLactin) |
|---|---|
| Description | Topical medication used to treat dry skin. Relieves itching and aids in healing skin in mild eczemas and dermatoses, itching skin, minor wounds, and minor skin irritations. Found in a variety of topical emollient lotions. |
| Adult Dose | Apply 1-3 times/d |
| Pediatric Dose | Apply as in adults |
| Contraindications | Documented hypersensitivity |
| Interactions | None reported |
| Pregnancy | C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus |
| Precautions | May cause stinging and burning at the site of application |
These agents have both anti-inflammatory (glucocorticoid) properties and salt-retaining (mineralocorticoid) properties. Glucocorticoids have profound and varied metabolic effects. In addition, these agents modify the body's immune response to diverse stimuli.
| Drug Name | Hydrocortisone (CortaGel, Cortaid, Dermacort) |
|---|---|
| Description | Adrenocorticosteroid derivative suitable for application to skin or external mucous membranes. Decreases inflammation by suppression of migration of polymorphonuclear leukocytes and reversal of increased capillary permeability. Can be a first-line treatment in this condition but can cause striae and skin thinning when used in axillary or groin areas. |
| Adult Dose | Apply qd/bid |
| Pediatric Dose | Not established |
| Contraindications | Documented hypersensitivity; viral, fungal, and bacterial skin infections |
| Interactions | None reported |
| Pregnancy | C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus |
| Precautions | Prolonged use, applying over large surface areas, applying potent steroids, and using occlusive dressings may increase systemic absorption of corticosteroids and may cause Cushing syndrome, reversible HPA-axis suppression, hyperglycemia, and glycosuria; use with caution in axillary and groin areas (can cause striae and skin thinning) |
Once the condition resolves and the inciting substances are avoided, granular parakeratosis does not tend to recur. However, sometimes, it has a chronic and relapsing course. Patients should not use occlusive compounds and should avoid excessive washing of axillary areas, groin, or other affected areas.
The prognosis is good with any form of treatment and avoidance of the inciting factors. However, sometimes, granular parakeratosis resists treatment and has a chronic and relapsing course.
No medicolegal complications exist because granular parakeratosis is a benign condition whose symptoms include pruritus and, sometimes, a burning sensation. Additionally, ensure that the condition is not a bacterial or fungal condition or that a case clinically diagnosed as granular parakeratosis is not another inflammatory condition.
Granular Parakeratosis excerpt
Article Last Updated: Jan 29, 2008
