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Featured researches published by Maureen B. Poh-Fitzpatrick.


The American Journal of Medicine | 1979

Porphyria cutanea tarda. Clinical features and laboratory findings in 40 patients.

Marc E. Grossman; David R. Bickers; Maureen B. Poh-Fitzpatrick; Vincent A. DeLeo; Leonard C. Harber

Porphyria cutanea tarda is the most common disorder of porphyrin metabolism in the United States and Europe. This report presents the clinical, laboratory and pathologic features of 40 patients with porphyria cutanea tarda. Each patient was followed up for variable times during 1960-76 at the Clinical Research Center and the Dermatology Service of the Columbia-Presbyterian Medical Center; at the New York University Medical Center; or at the Rockefeller University Hospital. Earlier age at onset; diminution of alcohol ingestion as the major etiologic factor; and, an increased incidence in females indicate new environmental influences. The most frequently associated etiologic factor, aside from alcohol intake, was use of estrogens for contraception; postmenopausal syndrome; or treatment of prostatic carcinoma. Cutaneous findings in the patients included bullae (85%); increased skin fragility (75%); facial hypertrichosis (63%); hyperpigmentation (55%); sclerodermoid changes (18%); and, dystrophic calcification with ulceration (8%). Diabetes mellitus was found in 15%; systemic lupus erythematosus in 5%; elevated serum iron level in 62%; and, abnormal liver function test results in 60%. Histologic abnormalities were seen in liver biopsies of 34 patients. Phlebotomy is the treatment of choice. In 32 patients so treated, clinical remissions averaged 30.9 months. 31% (10 patients) had a relapse but additional phlebotomies resulted in 2nd remissions. Chloroquine and plasmaphoresis treatments were also briefly discussed.


The American Journal of Medicine | 1976

Erythropoietic protoporphyria 10 years experience

Vincent A. DeLeo; Maureen B. Poh-Fitzpatrick; Micheline M. Mathews-Roth; Leonard C. Harber

The clinical and laboratory findings in 32 patients with erythropoietic protoporphyria as well as a review of the pertinent literature on this relatively recently described form of porphyria are presented. The disease is thought to be transmitted in an autosomal dominant fashion with variable penetrance and was characterized in these 32 patients by the onset in childhood of burning (97 per cent) and itching (88 per cent) of the skin on exposure to sunlight. This was accompanied by edema (49 per cent) and erythema (69 per cent) of the exposed areas. Vesicles, petechiae and residual scarring occurred less frequently. Associated abnormalities included cholelithiasis (12 per cent), anemia (27 per cent) and abnormal liver function studies (4 per cent). Reports of associated liver disease including nine cases of fatal hepatic failure, are reviewed. Current methods of diagnosis as well as theories of pathophysiology of the disease are presented. Nineteen of 23 of these patients recently treated with beta-carotene responded with significant increase in their tolerance to sun exposure.


The New England Journal of Medicine | 1986

Complete Suppression of the Symptoms of Congenital Erythropoietic Porphyria by Long-Term Treatment with High-Level Transfusions

Sergio Piomelli; Maureen B. Poh-Fitzpatrick; Carol Seaman; Lawrence M. Skolnick; Walter E. Berdon

CONGENITAL erythropoietic porphyria is a rare autosomal recessive disorder of heme biosynthesis that is secondary to reduced (10 to 30 percent of normal) uroporphyrinogen cosynthase activity.1 In p...


The New England Journal of Medicine | 1978

Porphyria Cutanea Tarda in Two Patients Treated with Hemodialysis for Chronic Renal Failure

Maureen B. Poh-Fitzpatrick; Neil Bellet; Vincent A. DeLeo; Marc E. Grossman; David R. Bickers

THERE have been several reports of a cutaneous blistering eruption occurring in patients with chronic renal failure undergoing hemodialysis1 2 3 4 5 that clinically and histopathologically resemble...


Journal of The American Academy of Dermatology | 1982

Porphyrin levels in plasma and erythrocytes of chronic hemodialysis patients

Maureen B. Poh-Fitzpatrick; Allan E. Sosin; James Bemis

Plasma porphyrins and free erythrocyte protoporphyrins were measured in sixty-two chronic hemodialysis patients. Plasma porphyrins were significantly elevated in these patients and overlapped the lower portion of the range observed in twenty-four patients with porphyria cutanea tarda. Free erythrocyte protoporphyrins were moderately elevated in four patients. Overall, these values were not statistically different from values for a control group of specimens from fifty ambulatory dermatology patients. However, they were, on average, lower than the normal values previously determined for the method used.


Journal of The American Academy of Dermatology | 1983

Hydroa vacciniforme: Induction of lesions with ultraviolet A

Charles L.G. Halasz; Eileen Enny Leach; Robert R. Walther; Maureen B. Poh-Fitzpatrick

Hydroa vacciniforme is a rare photosensitivity disorder with onset in childhood. The distinctive lesion is a vesicle which heals with scarring. We report a case of hydroa vacciniforme in which an abnormal minimal erythema dose to wavelengths of 322 to 370 nm within the ultraviolet A (UVA) range was demonstrated. Vesicles could be induced only with multiple exposures to UVA. Increased tolerance to UVA erythema was induced by multiple UVB exposures, although tanning was poor. Of note were the presence of several halo nevi and a history of the loss of ability to tan. The clinical features and appropriate laboratory evaluation of hydroa vacciniforme are reviewed.


The New England Journal of Medicine | 1987

Hepatoerythropoietic porphyria: clinical, biochemical, and enzymatic studies in a three-generation family lineage

Arnold C. Toback; Shigeru Sassa; Maureen B. Poh-Fitzpatrick; Jay Schechter; Edith Zaider; Leonard C. Harber; Attallah Kappas

Hepatoerythropoietic porphyria is caused by a marked deficiency in the activity of uroporphyrinogen decarboxylase, an enzyme that is essential for heme biosynthesis. It has been hypothesized that uroporphyrinogen decarboxylase deficiency is inherited as a homozygous defect in the disease. This suggestion has been supported by reports of a deficiency of the enzyme in parents of patients with the disorder. Further confirmation would be provided by demonstrating a similar uroporphyrinogen decarboxylase deficiency in the offspring of such patients. This study follows the enzymatic defect throughout three generations of a family in which a second-generation male was shown to have hepatoerythropoietic porphyria. Detailed biochemical and enzymatic analyses revealed a moderate deficiency of uroporphyrinogen decarboxylase in both the probands parents and in his three children, all of whom were asymptomatic. The mildness of the clinical symptoms in the proband correlated with a higher level of residual enzyme activity than that in previously described patients. We conclude that clinically manifested hepatoerythropoietic porphyria results from the homozygous inheritance of a defect in the uroporphyrinogen decarboxylase gene, that the severity of clinical symptoms is probably related to the level of residual enzyme activity, and that the genetic defect of uroporphyrinogen decarboxylase in hepatoerythropoietic porphyria can be heterogeneous.


Analytical Biochemistry | 1980

High-pressure liquid chromatography of plasma free acid porphyrins.

Maria O. Longas; Maureen B. Poh-Fitzpatrick

Abstract The separation and quantitation of plasma free acid porphyrins by high-pressure liquid chromatography and fluorescence is described. Porphyrins were extracted from plasma in a simple manner with a recovery >90%. They were separated by high-pressure liquid chromatography on a silica gel (10 μm) column, using a gradient of acetone:dilute acetic acid. Resolution of seven free acid porphyrin standards including coproporphyrins I and III, but not uroporphyrins I and III, was achieved in 12 min at picomolar concentrations. Plasma of patients with erythropoietic protoporphyria displayed protoporphyrin. Uroporphyrin was the only porphyrin found in plasma of eight patients with porphyria cutanea tarda. Normal plasma contained small amounts of uroporphyrin and/or traces of protoporphyrin.


Journal of Clinical Investigation | 1977

Comparative Study of Protoporphyrins in Erythropoietic Protoporphyria and Griseofulvin-Induced Murine Protoporphyria: BINDING AFFINITIES, DISTRIBUTION, AND FLUORESCENCE SPECTRA IN VARIOUS BLOOD FRACTIONS

Maureen B. Poh-Fitzpatrick; Angelo A. Lamola; Gregory L. Zalar; Mark Weinstein; Frank Doleiden; Maria Freeman

Excess erythrocyte protoporphyrins of human congenital erythropoietic protoporphyria and of griseofulvin-induced murine hepatic protoporphyria were found to be associated with hemoglobin and stroma fractions in similar relationships. More than 99.5% of total erythrocyte protoporphyrin was bound to hemoglobin in each case. However, profound differences were found when protoporphyrin concentration was measured in erythrocytes that had been segregated into populations of progressive age on discontinuous density gradients. In erythropoietic protoporphyria, porphyrin content diminished rapidly with age; in murine protoporphyria, the aging erythrocyte populations became progressively more porphyrin rich. In vitro diffusion of protoporphyrin from plasma across the intact erythrocyte membrane was demonstrated. The equimolar binding affinity of protoporphyrin to hemoglobin was shown to be 40 times that of protoporphyrin to serum albumin. This strong affinity provides the driving force for the observed transmembrane diffusion, and explains the high erythrocyte/plasma porphyrin ratio in murine hepatic protoporphyria. The opposite rapid efflux of intra-erythrocytic protoporphyrin into plasma previously shown in uncomplicated erythropoietic protoporphyria occurs despite this strong hemoglobin affinity, implying continuous efficient clearance of protoporphyrin from plasma by the liver. Furthermore, these and other data suggest that a hepatic synthetic source for any significant fraction of the blood protoporphyrin in erythropoietic protoporphyria is highly improbable.


Gastroenterology | 1985

Protoporphyrin Metabolic Balance in Human Protoporphyria

Maureen B. Poh-Fitzpatrick

Short-term maintenance of different stable steady state balances for protoporphyrin production, accumulation in erythrocytes and plasma, and fecal excretion was demonstrated in 5 patients with uncomplicated protoporphyria in whom red blood cell, plasma, and fecal protoporphyrin levels were determined on 5-7 sequential days. The patients were hospitalized in a research unit for dietary control and standardization of specimen collection. Each patient was found to quantitatively partition protoporphyrin among these compartments in a pattern that was reproducible from day to day, and characteristic for that patient. These observations partially substantiate a previously proposed hypothesis that protoporphyrin partitioning patterns may provide a criterion for prospective classification of these patients into groups that may ultimately be shown to have different risk for development of symptomatic liver disease.

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Vincent A. DeLeo

University of Southern California

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Katrin Kalka

University of Düsseldorf

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