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C L Goh

Publications and source records attributed to C L Goh.

At least 73 records · Page 4Linked to original sources

One-year review of pityriasis rosea at the National Skin Centre, Singapore.

Pityriasis rosea is a common, acute, self-limited papulosquamous eruption of possible viral aetiology. The aim of this study was to describe the profile of pityriasis rosea seen at a referral skin centre in Singapore. A retrospective chart review was conducted of all the patients with a diagnosis of pityriasis rosea seen during 1996. There were 368 patients; their ages ranged from 9 months to 82 years with a peak in the 20 to 29 years age group. There were slightly more males (1.2:1). The clinic incidence was 6.5 per 1000 cases. No ethnic predilection was noted and cases were seen evenly throughout the year. About a quarter of the patients gave a history of a viral infection shortly before or during the occurrence of the rash. Most cases had a typical truncal distribution. The herald patch was observed in 63 patients (17%). Inverse distribution involving mainly the extremities were seen in 22 cases (6%) and eczematised lesions were noted in 20 cases (5.4%). The two main differential diagnoses considered were tinea infection and secondary syphilis. A fungal scrape and a rapid plasma reagin test were done in 58 and 59 patients, respectively, and the results were negative. Treatment was symptomatic and consisted of topical steroids and antihistamines. Thirty patients (8%) were given oral prednisolone for extensive eruptions. The pattern of pityriasis rosea in Singapore is similar to that reported in other countries except for a male predominance and absence of monthly variation. A lower incidence and an older group of patients were also seen in our series as compared to African patients.

Adolescent↗

The epidemiology of atopic dermatitis at a tertiary referral skin center in Singapore.

Atopic dermatitis is a common chronic, relapsing, pruritic ecematous skin condition with a predilection for the flexural areas and occurs in patients with a personal or family history of atopy. The aim of this study is to describe the profile of atopic dermatitis seen at the National Skin Centre in Singapore. A retrospective chart review was conducted of all the patients with atopic dermatitis seen during the first six months of 1994. There were 492 patients whose ages ranged from one month to 74 years with an equal sex ratio. The prevalence was 2%. The onset of the disease occurred before the age of 10 years in 61.2% of patients. In 13.6% of the patients, the onset was after the age of 21 years. Two hundred and fifty-four patients (52%) had "pure" atopic dermatitis without concomitant respiratory allergies. Two hundred and thirty-eight patients (48%) suffered from a "mixed" type, with 23% having allergic rhinitis, 12% having asthma and 13% having both asthma and allergic rhinitis. Two hundred and thirty-one patients (47%) had at least one first-degree family member with atropy: atopic dermatitis (17%), asthma (15%) and allergic rhinitis (15%). Most of the patients, 416 (84.5%), had subacute eczema at presentation. Ichthyosis vulgaris was present in 38 patients (8%) and pityriasis alba in 13 patients (3%). The most common infective complication was bacterial infection (impetiginized eczema, folliculitis, cellullitis) present in 95 patients (19%) followed by viral infections (eczema herpeticum, viral warts and molluscum contagiosum) in 17 patients (3%). Allergies were noted in 43 patients (9%) based on the history given. The most common was drug allergies (penicillin and co-trimoxazole) in 28 patients followed by food allergies in 11 patients. Common aggravating factors reported include heat, sweating, stress, thick clothing and grass intolerance. Most patients could be controlled with a fairly simple regimen of moisturizers, topical steroids and antibiotics for acute flares. Short courses of systemic steroids were used in 78 patients (16%). Three patients were treated with phototherapy, Two on UVAB and one on PUVA. The pattern of atopic dermatitis in Singapore is similar to that reported in the Western literature except for a lower prevalence and a significant proportion of adult onset atopic dermatitis.

Adolescent↗

Contact allergy in Singapore.

Contact allergy, viz. allergic contact dermatitis, photo-allergic contact dermatitis and contact urticaria, is a well-studied sub-specialty of dermatology in Singapore. Over the years, numerous studies and anecdotal reports on the subject have been published in both international and local refereed journals. This article reviews the epidemiological data on patch testing and photo-patch testing in Singapore. It also summarizes published clinical reports on important contact allergens that are found in both non-occupational and occupational setting.

Adult↗

Cutaneous manifestations of chronic arsenicism: review of seventeen cases.

BACKGROUND: Cutaneous complications arising from exposure to Chinese proprietary medicines known to contain inorganic arsenic have been rarely reported. OBJECTIVE: Our purpose was to study the nature, incidence, and sequelae of patients with chronic arsenicism and to review the literature on arsenic-induced skin diseases. METHODS: Case records of patients with cutaneous lesions related to chronic arsenicism seen from January 1990 to December 1996 were reviewed. Patients were interviewed and a complete skin and systemic examination was performed. Data on demography, history of arsenic ingestion, and type and distribution of skin lesions and visceral malignancy were collated. RESULTS: Seventeen Chinese patients (11 men, six women) were identified; their mean age was 64.5 years. Fourteen patients (82%) had exposure to Chinese proprietary medicines known to contain inorganic arsenic, and three had environmental arsenic exposure from well water. The mean age of these 14 patients was 17.6 years; mean duration of arsenic intake was 6.4 years. Seventeen patients had Bowen's disease; of these, 70% had 2 to 10 lesions. Of the 17 patients with arsenical keratoses on the palms, 76% had 2 to 10 lesions. Of the 14 patients (82%) with plantar arsenical keratoses, 64% had 11 to more than 50 lesions. Eleven patients (65%) had macular hypopigmentation. Seven patients (41%) had 11 squamous cell carcinomas (SCCs); three of the seven had more than one lesion. Fifty-five percent of SCCs arose from preexisting keratotic lesions (n = 4) or Bowen's disease (n = 2), and 45% arose de novo. One patient each (6%) had multiple basal cell carcinomas, laryngeal carcinoma, and metastatic SCC. The latency periods for the development of arsenical keratoses, Bowen's disease, and SCC were 28, 39, and 41 years, respectively. Patients with SCC were significantly older at the start of arsenic exposure and had significantly more palmar arsenical keratoses than those without SCC. CONCLUSION: Exposure to Chinese proprietary medicines containing inorganic arsenic poses a risk for the development of cutaneous and systemic malignancies. Long-term follow-up is necessary for tumor detection because of long latency periods. Surveillance programs are important to restrict the sale of Chinese proprietary medicines that may contain inorganic arsenic.

Aged↗

Epidemiology and in vitro activity of antimycotics against candidal vaginal/skin/nail infections in Singapore.

BACKGROUND: Candidal infections of the skin/nails and vagina are very common worldwide. Various in vitro test systems are available to help to determine the antifungal activity of drugs. The minimum inhibitory concentration (MIC) is a standard measure of the in vitro potency of drugs against yeasts. METHODS: Vaginal smears and skin/nail scrapings of 50 consecutive patients with candidal vaginitis and 46 consecutive patients (28 women, 18 men) with cutaneous/nail candidosis were used in the study. Direct microscopy and culture from vaginal smears and skin scrapings were performed on all patients. The MICs were determined using the broth dilution method. RESULTS: For vaginal candidosis, the mean age of the patients was 28.2 years (range, 9-49 years). Candida albicans accounted for 58% of the isolates, C. glabrata for 32%, C. tropicalis for 6%, and C. parasilosis for 4%. At the MIC of < or = 4 mg/L, 65-95% of C. albicans, 66-94% of C. glabrata, 33-100% of C. tropicalis, and 0-50% of C. parasilosis were susceptible to the drugs tested (ketoconazole, itraconazole, nystatin, amorolfine, clotrimazole, and miconazole). For cutaneous/nail candidosis, the mean age of the patients was 45 years (range, 19-82 years). C. albicans made up 59% of the isolates, C. parasilosis 20%, C. krusei 13%, C. glabrata 4%, and C. tropicalis 4%. At the MIC of < or = 4 mg/L, 59-96% of C. albicans, 100% of C. glabrata, 83-100% of C. krusei, 89-100% of C. parasilosis, and 100% of C. tropicalis were susceptible to the drugs tested (ketoconazole, itraconazole, nystatin, amorolfine, clotrimazole, and miconazole). CONCLUSIONS: C. albicans is the most common Candida species causing cutaneous/nail and vaginal candidosis in Singapore. The in vitro antifungal activities of ketoconazole, itraconazole, nystatin, amorolfine, clotrimazole, and miconazole are similar against the various Candida species. C. parasilosis in vaginal candidosis appears to be less susceptible. Here, itraconazole and amorolfine may be more effective.

Adolescent↗

Sezary syndrome: a case report and a review of the molecular pathomechanism and management.

Sezary syndrome, one of the cutaneous T-cell lymphomas, is a rare cause of generalised exfoliative dermatitis. We report a case of Sezary syndrome in a 64-year-old man who had persistent erythroderma for four years and who subsequently developed inguinal lymphadenopathy and marked leukocytosis. We review the pathomechanism and management of this rare condition.

Humans↗

Occupational chromate allergy in Singapore: a study of 87 patients and a review from 1983 to 1995.

BACKGROUND: The prevalence of chromate allergy among all patients tested at the Contact and Occupational Dermatoses Clinic at the National Skin Centre in Singapore had fallen progressively from 1983 to 1989. Chromate has also become a less common occupational allergen because of the decline in the number of cases of allergic contact dermatitis from cement. OBJECTIVE: The aim of this report was to study and update the epidemiology of occupational chromate allergy among workers seen in a tertiary dermatology referral centre in Singapore from 1990 to 1995 and to review the changing trends of occupational chromate allergy in our local setting since 1983. The occurrence of concomitant contact allergens among was also studied. METHODS: All patients diagnosed to have occupational allergic contact dermatitis together with positive reactions to chromate, at the Joint Occupational Dermatosis Clinic at the National Skin Centre in Singapore, between January 1990 to December 1995, were included. Causes of chromate allergy and frequency of occurrence of concomitant contact allergens among construction and nonconstruction workers were compared. RESULTS: Eight hundred and fifty workers were seen during the 6-year-study period. Six hundred and thirty three (74.5%) were diagnosed to have occupational contact dermatitis, of which 257 (40.6%) had allergic contact dermatitis. Eighty-seven (33.8%) of these workers had positive reaction to chromate on patch testing. Ninety-five percent of these workers were men with a mean age of 33.4 years. The construction industry contributed 59% of the workers with chromate allergy. Cement (61%) remained the most common source of chromate allergy in our workers, and chromate from sources other than cement (39%) accounted for the rest. Of workers allergic to chromate from cement, 96% (51 of 53) came from the construction industry. Sixty percent of the workers with chromate allergy had concomitant contact allergens and the coexistence of two or more allergens was significantly more common among nonconstruction workers (53%) than construction workers (22%). The three most common concomitant contact allergens were cobalt (28%), rubber chemicals (21%) and nickel (18%). Nonconstruction workers had significantly higher rates of nickel allergy (36% v 6%) than construction workers (P < .03). Simultaneous reactivity to cobalt and nickel was also significantly more common among nonconstruction workers (22%) than construction workers (6%) (P < .03). CONCLUSION: Chromate has progressively become a less common occupational allergen at the National Skin Centre in Singapore from 1983 to 1989, because of a progressive fall in the number of cases of allergic contact dermatitis from cement. However, our study showed that occupational chromate allergy had now increased from 1990 to 1995, because of an increase in chromate allergy from sources other than cement. Chromate allergy from cement is declining, although still frequent, and sources other than cement are increasing in recent years. Concomitant nickel allergy, as well as simultaneous nickel and cobalt allergies, were more common among nonconstruction workers than construction workers.

Adult↗

Sunscreen allergy in Singapore.

We report the epidemiology of sunscreen allergy over a period of 5 years at the National Skin Centre. A total of 61 patients with suspected allergy to sunscreen underwent patch or photopatch testing to our sunscreen series from 1992 to 1996. The results were retrospectively analysed and evaluated. Out of these 61 patients, 5 were found to have positive patch test reactions to sunscreens. 2 were photoallergic, and 3 were allergic to active ingredients in sunscreens. The main causative allergens were 2-ethylhexyl-4-methoxycinnamate (Parsol MCX) and 2-hydroxy-4-methoxybenzophenone (oxybenzone). We conclude that sunscreen contact allergy is uncommon in our practice.

Adult↗

Allergic contact dermatitis to epoxy resin in a hemodialysis cannula.

A patient with chronic renal failure on hemodialysis presented with dermatitis, particularly over the arteriovenous fistulae sites on the forearm. Patch testing revealed a positive reaction to epoxy resin present in the glue that fixed the needle of the hemodialysis cannula.

Allergens↗

Comparing treatment response and complications between podophyllin 0.5%/0.25% in ethanol vs podophyllin 25% in tincture benzoin for penile warts.

AIM: The aims of this study were to: 1) ascertain if podophyllin resin in 0.5% [PE(0.5%)] and 0.25% [PE(0.25%)] in ethanol (PE) self-applied sequentially for 3 days with 4 days break cycle is as effective as supervised podophyllin 25% in tincture benzoin (PB) applied in the clinic biweekly in treating penile warts and 2) ascertain if PE causes less skin irritation than PB. METHODS AND RESULTS: The clearance rate of penile warts was 36.4% (4/11) in PE (0.5%) treated group, 66.7% (4/6) in the PE (0.25%) treated group and 33.3% (6/18) for PB treated group after 1 week (ns). The wart clearance rate at 6 weeks for PE (0.5%) treated group, PE (0.25%) treated group and PB treated group were 81.8% (9/11), 100% (6/6) and 83.3% (15/17) respectively (ns). There were 47 individual warts on the penis of the 17 patients in the PE treated group and 58 individual warts on the penis of the 18 patients in the PB treated group. Based on the response of individual warts to the 2 treatment regimens, the clearance rate was 42.6% (20/47) for the PE treated group and 25% (15/56) for the PB treated group after 1 week treatment (ns). At 6 weeks follow-up, the clearance rate for the PE treated group and the PB treated group were 85.1% (40/47) and 73.2% (41/56) respectively (ns). Skin irritation including superficial erosions, pain and itch were observed in 47% (8/17) in patients treated with PE compared to 38.9% (7/18) in patients treated with PB (ns) during the 6 weeks follow-up period. The clearance rate of patients treated with PE (0.25%) was compared to those treated with PE (0.5%). Four out of six of PE (0.25%) treated patients had clearance of warts after 1 week and 100% clearance at the end of 6 weeks. None experienced any skin irritation. CONCLUSION: This study demonstrates that 0.5% podophyllin (and possibly 0.25% podophyllin) in ethanol is effective in eradicating penile warts. It can be used by patients for self-treatment at home with greater convenience and is more cost effective than the conventional podophyllin 25% in tincture benzoin paint.

Adult↗

Corticosteroid contact hypersensitivity screening in Singapore.

BACKGROUND: Topical corticosteroids have been in use since 1957. Two percent to 5% of patients attending patch test (PT) clinics have problems with corticosteroid contact hypersensitivity. Controversies abound with regard to the choice of steroids in the standard battery, the method of patch testing and reading, and the ideal concentration and vehicle. OBJECTIVE: To assess betamethasone 17-valerate (1% pet.), fluocinolone acetonide (0.25% petrolatum [pet.]), and tixocortol pivalate (1% pet.) used in the authors' standard battery. METHODS: Data were analyzed for patients seen between January 1994 and December 1996 who had positive PT reactions to one or more of these steroids. RESULTS: 3,603 patients had standard PTs, of which 20 had positive reactions to one or more of these steroids. There were three positive reactions to betamethasone 17-valerate, 17 to tixocortol, and none to fluocinolone. On further patch testing to the authors' steroid battery, only one tixocortol-positive patient had a positive reaction to hydrocortisone (1% ethanol/ dimethyl sulfoxide [DMSO]). CONCLUSIONS: Corticosteroid allergy is found to be relatively uncommon in Singapore on the basis of this screening series. The frequency of negative reactions to fluocinolone acetonide is sufficiently low for this corticosteroid to be excluded from the authors standard series. The significance of positive tixocortol reactions remains unknown. From the review of other relevant literature, the authors recommend that budesonide be added to their present series. Testing betamethasone 17-valerate in 1% ethanol may yield more positive allergic reactions. Individuals with a positive allergic PT reaction to one corticosteroid should subsequently be tested to a full corticosteroid series.

Administration, Topical↗

Bacterial skin infections at a tertiary dermatological centre.

BACKGROUND: Bacterial skin infections are common clinical problems encountered in most fields of clinical medicine. Staphylococcus aureus and group A streptococci are common invaders of eczematous, traumatised or immunocompromised skin. Advances in pharmacology have introduced a wide array of new antibiotics into the physician's armamentarium, but the rising incidence of bacterial resistance continues to be a problem. A retrospective study was carried out on 331 patients at the National Skin Centre, Singapore, to establish the causes of common primary and secondary pyodermas, as well as to determine the antibiotic sensitivities of the microorganisms responsible. METHODS: A retrospective study of the medical records of 331 patients seen at the Centre for skin infections between October 1995 and May 1996 was done. Skin cultures and antibiotic sensitivity testing was carried out and the data analysed. Both primary pyodermas (impetigo, folliculitis, furuncles/carbuncles and cellulitis) and secondary pyodermas (infected ulcers and infected eczemas) were included. The results of bacterial isolation cultures and sensitivity of the organisms isolated to the commonly used antibiotics such as cloxacillin, penicillin, erythromycin and the tetracyclines were analysed. RESULTS: Staphylococcus aureus was the commonest organism isolated from both primary and secondary pyodermas, accounting for 67% and 46.7% of the organisms isolated, respectively. There was no significant difference in the racial representation in each of the various skin infections, but there was a significantly greater female representation in the infected ulcers. The secondary pyodermas had a significantly higher incidence of gram negative organisms causing infections, as well as culture results showing multiple bacterial pathogens. The methicillin resistant strains of S. aureus were commoner in the secondary pyodermas, and accounted for 4.2% of the total organisms isolated and 7% of the total strains of S. aureus. The S. aureus had a high rate of resistance (89.5%) to penicillin and ampicillin, but was very sensitive (93%) to cloxacillin, cephalexin and cotrimoxazole. The incidence of erythromycin resistance was 18.7%. CONCLUSIONS: In patients with primary pyodermas, cloxacillin should be the first line antibiotic used, with erythromycin as a useful but less preferred alternative. The favoured combination of ampicillin and cloxacillin has little place in routine treatment of skin infections, except for cellulitis and infected eczemas. A cephalosporin can also be used in these conditions if single drug therapy is desired. The secondarily infected ulcers are difficult to treat and would probably require the use of combination therapy in view of frequent mixed infections.

Adolescent↗

A retrospective epidemiology study of contact eczema among the elderly attending a tertiary dermatology referral centre in Singapore.

AIM: The aim of this study was to examine the epidemiology of contact eczema in the elderly patients attending a skin clinic in Singapore. METHODOLOGY: This is a retrospective study on patients attending our skin clinic at the National Skin Centre. All patients older than 49 years old attending our Contact and Occupational Dermatoses Clinic between 1990 and 1993 were included in the study. The prevalence of contact eczema among different age groups (50-59 years, 60-69 years, and 70-79 years) were compared. Diagnosis of contact dermatitis was based on the clinical history, physical examination and relevant patch test reactions. Demographic data of the patients were collected and analysed. Chi-square test was used for statistical analysis. RESULTS: Two hundred and one patients who were older than 49 years old, were included in the study. There was no significant difference in the prevalence of personal history of atopy among the 3 age groups. There was no significant difference in the racial distribution of the 3 age groups. The proportion of patients who were occupationally active decreased with age (50% vs 23% vs 0% respectively). There was no significant difference in the proportion of patients with positive patch test reactions in the 3 age groups although the proportion appears to increase with age (68% vs 75% vs 75% respectively). Similarly, the proportion of patients with allergic contact dermatitis was slightly higher in the older age group although the difference was not statistically significant among the 3 age groups (32% vs 45% vs 39% respectively). The face (54%) and hands (31%) were the commonest sites of eczema in the younger age group (50-59 years age group) whereas the lower limbs (41%) and the upper limbs (33.3%) were the commonest sites of eczema in the older patients (70-79 years age group). Nickel allergy was significantly more common in the younger age group (23% vs 17% vs 14% respectively). Medicament allergy (clioquinol-mix) and medicament related allergens e.g. balsam of Peru and fragrance-mix and para-phenylenediamine were slightly more prevalent in the older patients. CONCLUSIONS: The findings appear to indicate that the prevalence of allergic contact dermatitis is higher in older patients and that contact dermatitis tends to occur on the extremities in older patients than younger patients.

Aged↗

Retrospective study of the epidemiology of nodular vasculitis followed up in the National Skin Centre, Singapore.

A seven-year retrospective study was done on histologically proven nodular vasculitis presenting at the National Skin Centre, Singapore. We collected 25 patients and found that they differed from the classical European model. They most commonly involved the shins and did not ulcerate. A tuberculous aetiology accounted for 28% of cases. Useful indicators of tuberculosis were a past history of tuberculosis, an abnormal chest X-ray and a strongly positive Mantoux test.

Adolescent↗

Malignancy in adult dermatomyositis.

BACKGROUND: Dermatomyositis has been reported to be associated with malignancies in 15%-34% of patients in Western countries, but in as many as two-thirds of patients in Singapore. The aim of this study was to determine whether a diagnostic measure could be helpful in the diagnosis of a malignancy in patients with dermatomyositis. METHODS: This is a retrospective study on 38 adult patients with dermatomyositis that were seen over a 6-year period from 1989 to 1994. RESULTS: All the patients presented with cutaneous features that suggest the clinical diagnosis of dermatomyositis; however, not all cases show all the key features of the disease. Of the studied patients, 86.8% were noted to have photosensitivity as a key cutaneous presentation. Thirty (78.9%) of our patients were above the age of 40 years, and 12 (31.6%) of these were found to have an associated malignancy. Nasopharyngeal carcinoma was the most commonly associated malignancy (38.4%) in our study population. CONCLUSIONS: In our study population, otorhinolaryngologic screening is an essential investigation for the evaluation of dermatomyositis in association with malignancy.

Adolescent↗