Punctate keratoses of the palms and soles and keratotic pits of the palmar creases O. J. Rustad, MD,a and J. Corwin Vance, MDa, b Minneapolis, Minnesota Punctate keratoses of the palms and soles and keratotic pits of the palmar creases are frequently confused. A prospective study of 283 patients revealed a prevalence of 11% and 3%, respectively, in a metropolitan county hospital dermatology clinic.Punctate keratoses of the palms and soles and keratotic pits of the palmar creases are similar in size, number of lesions per palm, aggravation by trauma, and predominance in blacks and in men. These entities are different in appearance, distribution, age at onset, prevalence,symptoms, and prognosis.Punctate keratosis of the palms and solesand keratotic pits of the palmar creases should be considered independent entities. To help eliminate confusion, we propose that punctate keratoses refer only to the hyperkeratotic papules scattered diffuselyin the palms and occasionally in the soles and that keratotic pits of the palmar creases refer only the hyperkeratotic, conical depressions confined to the palmar creases. (J AM ACAD DERMATOL 1990; 22:468-76.) Punctate keratoses of the palms and soles are common lesions that are frequently overlooked. Keratotic pits ofthe palmar creases are less common and are frequently confused with punctate keratosis ofthe palms and soles, primarily, we believe, because of the inadequate terminology for these disorders. Punctate keratosis of the palms and soles has been referred to as "punctate keratoderma,"! "keratodermia punctata.t' White M>F Yes Yes
1-5 1-42(1-20) [8.5 (2.3)] Black> White M>F Yes Yes/No
Roundto oval, dome-shaped papules 2:1 11 (7-62) Left hand and hypothenar eminence
Round to oval pits
50 15-68 (15-60) [41] . 39 Itch Stable
Sporadic, (autosomal dominant) Papule (pyknotic, vacuolated epithelium; basallayer spongiosis, nuclear hydrops; dilated, occlusion of sweat ducts, blood vessels and lymph vessels) (Nucleolemma in prominent nucleoli of basal and spinous layers) Longitudinal nail dystrophy (onychogryphosis, onychomadesis, hyperpigmentation and blistering, hypopigmentation, lichen nitidus, knuckle pads, and warts)
"""'1:1 3 (0.05-56) Medial transpalmar and proximal interphalangeal joint creases 30 15-40 (19-49) [25] 88 Pain Morelikely than PK to increase in No. and size Uncertain
Pit, morefrequently associated with sweat ducts
(Unremarkable) Dupuytren's contacture, striatekeratoderma, knuckle pads (pterygium inversum unguis, dermatitis herpetiformis, psoriasis)
*Parentheses denote information from previous authors. be found concurrently with PK of the palms.l" soles,I9, 27 and with comedo-like lesions on the feet.10 Occasionally they can become scaling, ill-defined, ovalcraters withperipheralhyperpigmentation. One author 38 has reported a prodromal "ache" at the site where a pit wouldsubsequentlydevelop, followedby the developmentof a painful, scalingpapule. No evidence of systemic abnormalitiesb- " or of lesions elsewhereon the bodyhas been found.14 KPPC may
remain unchanged but frequently increase in size and number. They are rarely more than an annoyance, but the tenderness'" or the pain19 associated with KPPC may be so severe as to require surgical intervention if the process is localizedl'v'? or if a change of occupation if more diffuse-" Therapy with keratolytic agents or with retinoids has improved the condition only temporarily. 10, 13,40 The differential diagnosis varies for each condi-
Volume22 Number 3 March 1990
tion. For PK the differential diagnosis includes arsenic keratoses, verrucae vulgaris, lichen planus, secondary syphilis, linear epidermal nevus, keratosis follicularis, basal cell nevus syndrome, clavi, calluses, psoriasis, Cowden's disease, acrokeratosis verruciformis of Hopf, acrokeratoelastoidosis costa, lipid proteinosis, prurigo nodularis, pachyonychia congenita, epidermodysplasia verruciformis, hyperkeratosis lenticularis perstans, scabies, benign familial pemphigus, tyrosinemia, eccrine poromas," yaws, keratoma plantare sulcatum, hyperkeratosis foUicularis et parafollicularis in eutem penetrans, angiokeratoma.! punctate palmoplantar keratoses acuminate." hereditary painful calluses,42 punctate porokeratotic keratoderma.f punctate porokeratosis of the palms and soles,28,44,45 focal acral hyperkeratosis.f and gouty tophi.f For KPPC the differential diagnosis includes basal cellnevus syndrome, porokeratosis of Mibelli, acrokerato elastoidosis.P focal acral hyperkeratosis,46 punctate xanthoma.f and keratosis follicularis. The cause of PK and KPPC remains unknown. Several etiologic theories have been proposed for PK. One theory previously advanced was an abnormal keratinization of the sweat duct. The hyperkeratinization was thought to be due to an inherent process in the ducts-"or due to a drug.2, 21 The sweat ducts in our specimens were histologically normal, however, and not everyPK or KPPC was associated with a duct. We were unable to elicit a consistent history of any possible offending drug. A viralcause has been proposed because of the possible relationship to virally associated carcinomas (lung and bladder) and because of a history of recalcitrant warts in some patients.21,23,30 Although PK may resemble verrucae clinically, no histologic evidence supports this theory. 23,28 Specific analysis for viral DNA content will be necessary to excludethis possibility. A suboptimal level of provitamin A or ,8-carotene has been proposed as a link between the development of cancer and PK, because of the involvement of vitamin A in cellular differentiation and ,8-carotene's ability to quench singlet oxygen.i? If such a systemic abnormality were present, it would be difficult to explain why a healthy population is generally afflicted with PK and KPPC and why these processes are so localized. Finally, both PK and KPPC have been regarded by some in-
Punctate keratoses and keratotic pits 475 vestigators as an abnormal variant of callus formation. 16,18 PK and KPPC seem to be due to an abnormal localized, hyperproliferative response in predisposed persons inducedpossibly by trauma. Our reasoning includes the clinical observation of their association with manual labor and their characteristic distribution on the palms and soles. The predominance of lesions on the ulnar half of the palm in both entities may be anticipated because it is the more powerful halfofthe hand.Thedominanthand (the righthand in most people) is usually responsible for fine motor coordination, whereas the nondominant (usually the left hand) is the stabilizing hand. This predisposes the left hand, particularly the ulnar portion of the palm, to more trauma.50, 51 The overrepresentation of men in occupations involving manual labor may accountfor the difference in occurrence between the sexes. A hypermetabolic reactive process may be deduced from the histologic observations of hyperkeratosis with occasional parakeratosis and, in PK, an increased nucleolemma. PK and KPPC are dissimilar enough that they should be considered independent entities (Table III). To help eliminate confusion, we propose that punctate keratoses refer only to the hyperkeratotic papules that are seen scattered diffusely on the palms and occasionally the soles, whereas keratotic pits of the palmar creases refer only to the hyperkeratoticconical depressions confined to the palmar creases. REFERENCES 1. Brown Fe. Punctate keratoderma. Arch Dermatol 1971;104:682-3. 2. Chalmers Al, KamarSA.Keratodermia punctata. 1 Trop Med Hyg 1917;11:121-7. 3. Scott Ml, Costello Ml, Simuangco S. Keratosis punctata palmaris et plantaris. ArchDermatol Syph 1951;64:301-8. 4. Lorincz AL. Keratoma hereditarium dissipatum palmare et plantarewith cutaneous hornformation (Brauer) treated with lithium bromide [Society Transactions]. Arch Dermato1 Syph 1953;68:91. 5. Michael le. Keratoderma disseminatum palmaris et plantaris: its mode of inheritance. Arch Dermatol Syph 1933;27:78-88. 6. Dobson RL, Young MR, Pinto lS. Palmar keratoses and cancer. Arch Dermatol 1965;92:553-6. 7. Rhodes EL. Palmarand plantar seed keratoses andinternal malignancy. Br 1 Dermatol 1970;82:361-3. 8. Costello Ml, Gibbs RC. The palms and soles in medicine. Springfield, Ill.: Charles C Thomas, 1967:133-41. 9. Levin HM. Keratoderma disseminatum palmaris et plantaris. Arch DermatolI960;81:620-1.
Journal of the American Academy of Dermatology
476 Rustad and Vance 10. DilaimyMS, Owen WR, Sina B.Keratosis punctata of the palmar creases. Cutis 1984;33:394-6. 11. Schwartz RA, Rohas-Corona RR, Yu GSM, et al. Keratosis punctata of the palmar creases. Cutis 1983;32:75-7. 12. Harwell WB. Keratosis punctata. Arch Dermatol 976;112:255-6. 13. Phillips B. A case of keratodermia punctata. Br Med 1 1947;2:689. 14. Arnold HL. Hyperkeratosis penetrans: report of a case of a probablevariantof Kyrle'sdisease. Arch DermatolSyph 1947;55:633-8. 15. DupreA, Christol B, Bonafe Jl., et al. Pterygiuminversum unguis et atrophie ponctuee des plis palmaires. Dermatologica 1981;162:209-12. 16. Smith EB, letton RL. Punctate pits and keratoses of the palmar creases. South Med J 1970;63:1291-3. 17. Bean SF, Foxley EG, Fusaro RM. Palmar keratoses and internal malignancy. Arch DermatoI1968;97:528-32. 18. RosenT, MartinS. Palmaroddities. In:Atlas of'blackdermatology. Boston: Little,Brown, 1981:12-3. 19. WeissRM, Rasmussen JE. Keratosis punctata of the palmar creases. Arch DermatoI1980il16:669-71. 20. Buchanan RN. Keratosis punctata palmaris et plantaris. Arch Dermatol 1963;88:644-50. 21. Cuzick J, Harris R, Mortimer PS. Palmar keratoses and cancersof the bladder and lung. Lancet 1984;10:530-3. 22. LieberthalD. Disseminated palmar andplantar keratoderma. Arch Dermatol Syph 1926;14:655-61. 23. Johansson EA, Kariniemi AL, Niemi KM. Palmoplantar keratoderma of punctatetype [Abstract].J InvestDermatol 1975; 72:275. 24. Nexmand PH. Keratoderma palmareet plantare disseminatum. Dermatologica 1949;99:157-63. 25. Galloway J. Punctatekeratosis of the feet: twocasesoccurring in cousins-German. Br J Dermatol 1918;30:123-9. 26. Weiss RM, Cohen AD. Lichen nitidus of the palms and soles. Arch DermatoI1971;104:538-40. 27. StolmanLP, KopfAW, Garfinkel L. Are palmar keratoses asignofinternalmalignancy? ArchDermatol1970;101:525. 28. Rubenstein DJ, SchwartzRA, HansenRC, et al.Punctate hyperkeratosis of the palms and soles: an ultrastructural study. 1 AMACAD DERMATOL 1980;3:43-9. 29. ThankappanTP, HariIalKR, Zacharia J. Keratosis punctata of palmar creases [Case report]. Indian 1 Dermatol Venereol Lepr 1982;48:176-8. 30. Cartwright RA, GlashanRW. Palmar keratoses and bladder cancer [Letter]. Lancet 1984;1:563. 31. Stone 01, Mullins IF. Nail changes in keratosis punctata. Arch Dermatol 1965;92:557-8.
32. Pardo-Costello V, Pardo OA. Diseases of the nails. 3rd ed. Springfield, I1l.: Charles C Thomas, 1960:74. 33. ColeLA. Hypopigmentation with punctatekeratosisof the palms and soles. Arch DermatoI1976;112:998-1000. 34. Boss 1M, Matthews CNA, Peachy RDG, et al. Speckled hyperpigmentation, palrno-plantar punctate keratosesand childhood blistering: a clinical triad, with variable associations. Br 1 DermatoI1981;105:579-85. 35. MehreganAM, Hardin I. Generalized follicular hamartoma: complicated by multiple proliferating trichilemmal cysts and palmar pits. Arch DermatoI1973;107:435-8. 36. Schepart BS,Schwartz RA, SouthwickGl, et al. Dupuytren's diseasepresenting as palmar pits.1 Med 1978;9:34750. 37. CoupeR, Usher B. Keratosis punctata palmaris et plantaris. Arch DermatoI1963;87:91-5. 38. FischerRW, StampsP, SkipworthGB.A proposedvariant of hyperkeratosis penetrans. Arch Dermatol 1968;98:2702.
39. Sweitzer SE. Keratoderma punctatum. Arch Dermatol Syph 1923;8:687-94. 40. Ortega M, Quintana 1, Camacho F. Keratosispunctata of the palmar creases. 1 AMACAD DERMATOL1985;13:381-2. 41. Premalatha S, AugustineSM, YesudianP, et al. Punctate palmoplantarkeratosis acuminata: an unusual form of tuberculid. Int 1 Dermatol 1982;8:470-1. 42. Roth W, Penneys NS, Fawcett N. Hereditary painful callosities. Arch Dermatol 1978i114:591-2. 43. Friedman S1, Herman PS, Pittelkow MR, et al. Punctate porokeratotic keratoderma. Arch Dermatol 1988;124: 1678-82. 44. DowdPM, Harman RRM, BlackMM. Focalacral hyperkeratosis. Br 1 DermatoI1983;109:97-103. 45. Herman PS. Punctate porokeratotic keratoderma. Dermatologica 1973;147:206-13. 46. HimmelsteinR, Lynfield YL. Punctateporokeratosis. Arch Dermatol 1984;120:263-4. 47. Wilkerson MG. Case 40. Challenges in dermatology 1988;13:6-7. 48. Norman R, Genest1. Tuberoeruptive xanthomas:unusual presentation of type V hyperlipo-proteinemia. Cutis 1988;43:169-71. 49. Drijver M, Kromhout D. Might (pro-)vitamin A be involved in the relationbetween palmar keratosis and cancer of bladder and lung? [Letter]. Lancet 1984;1:643. 50. Parry CBW. Rehabilitation of the hand. 3rd ed. London: Butterworth, 1973:25-8. 51. Coilliet R. Hand pain and impairment. 3rd ed. Philadelphia: FA Davis Co, 1982:34-9.
1-5 1-42(1-20) [8.5 (2.3)] Black> White M>F Yes Yes/No
Roundto oval, dome-shaped papules 2:1 11 (7-62) Left hand and hypothenar eminence
Round to oval pits
50 15-68 (15-60) [41] . 39 Itch Stable
Sporadic, (autosomal dominant) Papule (pyknotic, vacuolated epithelium; basallayer spongiosis, nuclear hydrops; dilated, occlusion of sweat ducts, blood vessels and lymph vessels) (Nucleolemma in prominent nucleoli of basal and spinous layers) Longitudinal nail dystrophy (onychogryphosis, onychomadesis, hyperpigmentation and blistering, hypopigmentation, lichen nitidus, knuckle pads, and warts)
"""'1:1 3 (0.05-56) Medial transpalmar and proximal interphalangeal joint creases 30 15-40 (19-49) [25] 88 Pain Morelikely than PK to increase in No. and size Uncertain
Pit, morefrequently associated with sweat ducts
(Unremarkable) Dupuytren's contacture, striatekeratoderma, knuckle pads (pterygium inversum unguis, dermatitis herpetiformis, psoriasis)
*Parentheses denote information from previous authors. be found concurrently with PK of the palms.l" soles,I9, 27 and with comedo-like lesions on the feet.10 Occasionally they can become scaling, ill-defined, ovalcraters withperipheralhyperpigmentation. One author 38 has reported a prodromal "ache" at the site where a pit wouldsubsequentlydevelop, followedby the developmentof a painful, scalingpapule. No evidence of systemic abnormalitiesb- " or of lesions elsewhereon the bodyhas been found.14 KPPC may
remain unchanged but frequently increase in size and number. They are rarely more than an annoyance, but the tenderness'" or the pain19 associated with KPPC may be so severe as to require surgical intervention if the process is localizedl'v'? or if a change of occupation if more diffuse-" Therapy with keratolytic agents or with retinoids has improved the condition only temporarily. 10, 13,40 The differential diagnosis varies for each condi-
Volume22 Number 3 March 1990
tion. For PK the differential diagnosis includes arsenic keratoses, verrucae vulgaris, lichen planus, secondary syphilis, linear epidermal nevus, keratosis follicularis, basal cell nevus syndrome, clavi, calluses, psoriasis, Cowden's disease, acrokeratosis verruciformis of Hopf, acrokeratoelastoidosis costa, lipid proteinosis, prurigo nodularis, pachyonychia congenita, epidermodysplasia verruciformis, hyperkeratosis lenticularis perstans, scabies, benign familial pemphigus, tyrosinemia, eccrine poromas," yaws, keratoma plantare sulcatum, hyperkeratosis foUicularis et parafollicularis in eutem penetrans, angiokeratoma.! punctate palmoplantar keratoses acuminate." hereditary painful calluses,42 punctate porokeratotic keratoderma.f punctate porokeratosis of the palms and soles,28,44,45 focal acral hyperkeratosis.f and gouty tophi.f For KPPC the differential diagnosis includes basal cellnevus syndrome, porokeratosis of Mibelli, acrokerato elastoidosis.P focal acral hyperkeratosis,46 punctate xanthoma.f and keratosis follicularis. The cause of PK and KPPC remains unknown. Several etiologic theories have been proposed for PK. One theory previously advanced was an abnormal keratinization of the sweat duct. The hyperkeratinization was thought to be due to an inherent process in the ducts-"or due to a drug.2, 21 The sweat ducts in our specimens were histologically normal, however, and not everyPK or KPPC was associated with a duct. We were unable to elicit a consistent history of any possible offending drug. A viralcause has been proposed because of the possible relationship to virally associated carcinomas (lung and bladder) and because of a history of recalcitrant warts in some patients.21,23,30 Although PK may resemble verrucae clinically, no histologic evidence supports this theory. 23,28 Specific analysis for viral DNA content will be necessary to excludethis possibility. A suboptimal level of provitamin A or ,8-carotene has been proposed as a link between the development of cancer and PK, because of the involvement of vitamin A in cellular differentiation and ,8-carotene's ability to quench singlet oxygen.i? If such a systemic abnormality were present, it would be difficult to explain why a healthy population is generally afflicted with PK and KPPC and why these processes are so localized. Finally, both PK and KPPC have been regarded by some in-
Punctate keratoses and keratotic pits 475 vestigators as an abnormal variant of callus formation. 16,18 PK and KPPC seem to be due to an abnormal localized, hyperproliferative response in predisposed persons inducedpossibly by trauma. Our reasoning includes the clinical observation of their association with manual labor and their characteristic distribution on the palms and soles. The predominance of lesions on the ulnar half of the palm in both entities may be anticipated because it is the more powerful halfofthe hand.Thedominanthand (the righthand in most people) is usually responsible for fine motor coordination, whereas the nondominant (usually the left hand) is the stabilizing hand. This predisposes the left hand, particularly the ulnar portion of the palm, to more trauma.50, 51 The overrepresentation of men in occupations involving manual labor may accountfor the difference in occurrence between the sexes. A hypermetabolic reactive process may be deduced from the histologic observations of hyperkeratosis with occasional parakeratosis and, in PK, an increased nucleolemma. PK and KPPC are dissimilar enough that they should be considered independent entities (Table III). To help eliminate confusion, we propose that punctate keratoses refer only to the hyperkeratotic papules that are seen scattered diffusely on the palms and occasionally the soles, whereas keratotic pits of the palmar creases refer only to the hyperkeratoticconical depressions confined to the palmar creases. REFERENCES 1. Brown Fe. Punctate keratoderma. Arch Dermatol 1971;104:682-3. 2. Chalmers Al, KamarSA.Keratodermia punctata. 1 Trop Med Hyg 1917;11:121-7. 3. Scott Ml, Costello Ml, Simuangco S. Keratosis punctata palmaris et plantaris. ArchDermatol Syph 1951;64:301-8. 4. Lorincz AL. Keratoma hereditarium dissipatum palmare et plantarewith cutaneous hornformation (Brauer) treated with lithium bromide [Society Transactions]. Arch Dermato1 Syph 1953;68:91. 5. Michael le. Keratoderma disseminatum palmaris et plantaris: its mode of inheritance. Arch Dermatol Syph 1933;27:78-88. 6. Dobson RL, Young MR, Pinto lS. Palmar keratoses and cancer. Arch Dermatol 1965;92:553-6. 7. Rhodes EL. Palmarand plantar seed keratoses andinternal malignancy. Br 1 Dermatol 1970;82:361-3. 8. Costello Ml, Gibbs RC. The palms and soles in medicine. Springfield, Ill.: Charles C Thomas, 1967:133-41. 9. Levin HM. Keratoderma disseminatum palmaris et plantaris. Arch DermatolI960;81:620-1.
Journal of the American Academy of Dermatology
476 Rustad and Vance 10. DilaimyMS, Owen WR, Sina B.Keratosis punctata of the palmar creases. Cutis 1984;33:394-6. 11. Schwartz RA, Rohas-Corona RR, Yu GSM, et al. Keratosis punctata of the palmar creases. Cutis 1983;32:75-7. 12. Harwell WB. Keratosis punctata. Arch Dermatol 976;112:255-6. 13. Phillips B. A case of keratodermia punctata. Br Med 1 1947;2:689. 14. Arnold HL. Hyperkeratosis penetrans: report of a case of a probablevariantof Kyrle'sdisease. Arch DermatolSyph 1947;55:633-8. 15. DupreA, Christol B, Bonafe Jl., et al. Pterygiuminversum unguis et atrophie ponctuee des plis palmaires. Dermatologica 1981;162:209-12. 16. Smith EB, letton RL. Punctate pits and keratoses of the palmar creases. South Med J 1970;63:1291-3. 17. Bean SF, Foxley EG, Fusaro RM. Palmar keratoses and internal malignancy. Arch DermatoI1968;97:528-32. 18. RosenT, MartinS. Palmaroddities. In:Atlas of'blackdermatology. Boston: Little,Brown, 1981:12-3. 19. WeissRM, Rasmussen JE. Keratosis punctata of the palmar creases. Arch DermatoI1980il16:669-71. 20. Buchanan RN. Keratosis punctata palmaris et plantaris. Arch Dermatol 1963;88:644-50. 21. Cuzick J, Harris R, Mortimer PS. Palmar keratoses and cancersof the bladder and lung. Lancet 1984;10:530-3. 22. LieberthalD. Disseminated palmar andplantar keratoderma. Arch Dermatol Syph 1926;14:655-61. 23. Johansson EA, Kariniemi AL, Niemi KM. Palmoplantar keratoderma of punctatetype [Abstract].J InvestDermatol 1975; 72:275. 24. Nexmand PH. Keratoderma palmareet plantare disseminatum. Dermatologica 1949;99:157-63. 25. Galloway J. Punctatekeratosis of the feet: twocasesoccurring in cousins-German. Br J Dermatol 1918;30:123-9. 26. Weiss RM, Cohen AD. Lichen nitidus of the palms and soles. Arch DermatoI1971;104:538-40. 27. StolmanLP, KopfAW, Garfinkel L. Are palmar keratoses asignofinternalmalignancy? ArchDermatol1970;101:525. 28. Rubenstein DJ, SchwartzRA, HansenRC, et al.Punctate hyperkeratosis of the palms and soles: an ultrastructural study. 1 AMACAD DERMATOL 1980;3:43-9. 29. ThankappanTP, HariIalKR, Zacharia J. Keratosis punctata of palmar creases [Case report]. Indian 1 Dermatol Venereol Lepr 1982;48:176-8. 30. Cartwright RA, GlashanRW. Palmar keratoses and bladder cancer [Letter]. Lancet 1984;1:563. 31. Stone 01, Mullins IF. Nail changes in keratosis punctata. Arch Dermatol 1965;92:557-8.
32. Pardo-Costello V, Pardo OA. Diseases of the nails. 3rd ed. Springfield, I1l.: Charles C Thomas, 1960:74. 33. ColeLA. Hypopigmentation with punctatekeratosisof the palms and soles. Arch DermatoI1976;112:998-1000. 34. Boss 1M, Matthews CNA, Peachy RDG, et al. Speckled hyperpigmentation, palrno-plantar punctate keratosesand childhood blistering: a clinical triad, with variable associations. Br 1 DermatoI1981;105:579-85. 35. MehreganAM, Hardin I. Generalized follicular hamartoma: complicated by multiple proliferating trichilemmal cysts and palmar pits. Arch DermatoI1973;107:435-8. 36. Schepart BS,Schwartz RA, SouthwickGl, et al. Dupuytren's diseasepresenting as palmar pits.1 Med 1978;9:34750. 37. CoupeR, Usher B. Keratosis punctata palmaris et plantaris. Arch DermatoI1963;87:91-5. 38. FischerRW, StampsP, SkipworthGB.A proposedvariant of hyperkeratosis penetrans. Arch Dermatol 1968;98:2702.
39. Sweitzer SE. Keratoderma punctatum. Arch Dermatol Syph 1923;8:687-94. 40. Ortega M, Quintana 1, Camacho F. Keratosispunctata of the palmar creases. 1 AMACAD DERMATOL1985;13:381-2. 41. Premalatha S, AugustineSM, YesudianP, et al. Punctate palmoplantarkeratosis acuminata: an unusual form of tuberculid. Int 1 Dermatol 1982;8:470-1. 42. Roth W, Penneys NS, Fawcett N. Hereditary painful callosities. Arch Dermatol 1978i114:591-2. 43. Friedman S1, Herman PS, Pittelkow MR, et al. Punctate porokeratotic keratoderma. Arch Dermatol 1988;124: 1678-82. 44. DowdPM, Harman RRM, BlackMM. Focalacral hyperkeratosis. Br 1 DermatoI1983;109:97-103. 45. Herman PS. Punctate porokeratotic keratoderma. Dermatologica 1973;147:206-13. 46. HimmelsteinR, Lynfield YL. Punctateporokeratosis. Arch Dermatol 1984;120:263-4. 47. Wilkerson MG. Case 40. Challenges in dermatology 1988;13:6-7. 48. Norman R, Genest1. Tuberoeruptive xanthomas:unusual presentation of type V hyperlipo-proteinemia. Cutis 1988;43:169-71. 49. Drijver M, Kromhout D. Might (pro-)vitamin A be involved in the relationbetween palmar keratosis and cancer of bladder and lung? [Letter]. Lancet 1984;1:643. 50. Parry CBW. Rehabilitation of the hand. 3rd ed. London: Butterworth, 1973:25-8. 51. Coilliet R. Hand pain and impairment. 3rd ed. Philadelphia: FA Davis Co, 1982:34-9.
