Biomedical subjects

Charoen Choonhakarn

Publications and source records attributed to Charoen Choonhakarn.

4 recordsLinked to original sources

PubMed2004

Lupus erythematosus tumidus.

BACKGROUND: Lupus erythematosus tumidus (LET) is a rare form of chronic cutaneous lupus erythematosus that characteristically presents as a succulent, erythematous plaques on sun-exposed areas. The histopathological change that primarily distinguishes LET from other variants of cutaneous lupus erythematosus is the lack of alterations of the dermo-epidermal junction and epidermis. Our purpose was to describe 15 cases of LET from Thailand. METHODS: The records of 15 patients diagnosed with LET at Srinagarind Hospital Medical School between 1995 and 2002 were reviewed on the following aspects: clinical manifestation, laboratory investigation, direct immunofluorescence study, phototesting, histopathological findings, clinical course, and treatment. RESULTS: All 15 patients consisted of 10 females and five males. The mean age at onset was 38.8 years. The lesions more commonly affect the face and trunk. One patient had concomitant discoid lupus erythematosus and two developed systemic involvement 4 and 6 months after LET. Direct immunofluorescence studies all showed negative results. Positive phototest reactions were detected in five of 10 tested patients: four with ultraviolet A and B and one with ultraviolet A only. Most patients responded well to chloroquine phosphate and the remainder successfully improved with methotrexate, topical and systemic corticosteroids. CONCLUSION: Our data demonstrate the features of LET that are repeatable and characteristic. Lupus erythematosus tumidus in this study was more common in women, and photosensitivity reactions of the patients were seen less frequently compared with those in the earlier report of Kuhn et al. Furthermore, two of 15 patients exhibited systemic involvement in the course of their disease.

Adolescent↗

PubMed2003

Cutaneous metaplastic synovial cyst.

Metaplastic synovial cyst of the skin is a recently recognized entity characterized by an intradermal nodule that usually occurs at the site of previous surgical trauma. Histologically, the lesion demonstrates a cystic structure with villous-like projections and a lining resembling hyperplastic synovium. We have studied two patients with rheumatoid arthritis, aged 46 and 55 years, who presented with cystic nodules localized on the thumb and great toes, respectively, without any history of previous trauma or surgical procedures performed in the areas. The presence of vimentin and CD 68 positivity of the cells lining the cyst walls supports the similarities between normal and metaplastic synovium. We hypothesize that constant pressure on the great toe, repeated manipulation of the finger, and chronic inflammation around the affected joints may have played roles in the pathogenesis of the lesions in our patients.

Arthritis, Rheumatoid↗

PubMed2002

Haplotype associations of the major histocompatibility complex with psoriasis in Northeastern Thais.

BACKGROUND: To evaluate the distributions of the human leukocyte antigen (HLA) at class I and II loci that may contribute to the genetic susceptibility to psoriasis patients in the north-eastern Thai population. MATERIALS AND METHODS: We analyzed the allelic frequencies of HLA class I and II by using the polymerase chain reaction-amplification refractory mutation system (PCR-ARMS) technique and polymerase chain reaction-single stranded conformation polymorphism (PCR-SSCP), respectively, in 140 north-eastern Thais with psoriasis that were sudivided into two groups: one with age at onset < 40 years (type I psoriasis; 95 cases) and the other with age at onset > 40 years (type II psoriasis; 45 cases). Three hundred healthy unrelated north-eastern Thais were used as controls. RESULTS: HLA-A*01, -A*0207, -A*30, -B*08, -B*13, -B*4601, -B*57, -Cw*01, -Cw*0602, and -DRB1*07 were positively associated with type I psoriasis, whereas HLA-A*24, -A*33, and -Cw*04 were negatively associated with type I psoriasis with statistical significance when compared to the controls. The Cw*0602 allele showed the strongest correlation with this type. In addition, the frequencies of HLA-A*0207, -A*30, -Cw*01, and -DRB1*1401 were significantly increased in type II psoriasis. HLA-A*207, -B*4601, -Cw*01, -DRB1*09, -DQB1*0303 (AH46.1), HLA-A*01-B*57-Cw*0602-DRB1*07-DQB1*0303 (AH57.1), and HLA-A*30, -B*13, -Cw*0602, -DRB1*07, and -DQB1*02 (AH13.1) were identified as high-risk major histocompatibility complex (MHC) halotypes for psoriasis patients in the early onset group in north-eastern Thais. CONCLUSIONS: This study demonstrates not only the differential association between HLA markers and types of psoriasis according to age at onset, but also a newly found high-risk and a protective haplotype in Thai psoriasis patients.

Adult↗

PubMed2002

Familial amyloidosis cutis dyschromica: six cases from three families.

Amyloidosis cutis dyschromica, a rare form of primary cutaneous amyloidosis requiring histopathological confirmation, is characterized by generalized, asymptomatic hyperpigmentation intermingled with several hypopigmented spots without papulation, atrophy, and telangiectasia. Its onset usually begins before puberty. We describe six patients from three families, four male and two female. The mean age at onset was 10.2 years. Although the skin eruptions had developed extensively since childhood, systemic involvement was not evident even after long-term follow-up. Due to its unique and characteristic features, this condition should be considered as a separate entity and differentiated from other variants of primary cutaneous amyloidosis. The familial occurrence in our report suggests a genetic causal factor in this disease.

Adolescent↗