Tuesday, February 5, 2013

Porphyria Cutanea Tarda

Abstract:  50 yo man with erosions on dorsum of hands, arms, elbows, and scalp for six months.

HPI: This 50 year-old man reports he has had "blisters and sores" on dorsum of hands, arms, elbows, and scalp for six months.  He feels he is in otherwise good health, takes no meds by mouth and drinks 2 - 3 beers per day.  This man works outdoors as a carpenter so he gets lots of sun (although it is winter here). When he developed his initial lesions it was summertime.

O/E:  There are superficial erosions of the hands, elbows, and scalp.  No vesicles were noted.

Clinical Photos:



Lab: CBC normal
Chemistries:  SGOT 141 (normal 10 - 42)
SGPT  164  (normal 19 - 49)
Ferritin 486  (normal  220 - 250
Urinary Porphyrins:
Uroporphyrin:  1523 (normal < 22)
Coprophyrin: 450 (23 - 230)
Total Porphyrins  2675  (normal  31 - 139)
Hepatitis Serology and HIV tests willbe ordered.

Diagnosis:  Porphyria Cutanea Tarda

Plan:  Will probably treat with hydroxychloroquine

Questions: 

Reference:

1. Clin Gastroenterol Hepatol. 2012 Dec;10(12):1402-9
Low-dose hydroxychloroquine is as effective as phlebotomy in treatment of patients with porphyria cutanea tarda.
Singal AK, Kormos-Hallberg C, Lee C, Sadagoparamanujam VM, Grady JJ, Freeman DH Jr, Anderson KE.
Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, USA. aksingal@uab.edu
Abstract
BACKGROUND:  Porphyria cutanea tarda (PCT) is an iron-related disorder caused by reduced activity of hepatic uroporphyrinogen decarboxylase; it can be treated by phlebotomy or low doses of hydroxychloroquine. We performed a prospective pilot study to compare the efficacy and safety of these therapies.
METHODS: We analyzed data from 48 consecutive patients with well-documented PCT to characterize susceptibility factors; patients were treated with phlebotomy (450 mL, every 2 weeks until they had serum ferritin levels of 20 ng/mL) or low-dose hydroxychloroquine (100 mg orally, twice weekly, until at least 1 month after they had normal plasma levels of porphyrin). We compared the time required to achieve a normal plasma porphyrin concentration (remission, the primary outcome) for 17 patients treated with phlebotomy and 13 treated with hydroxychloroquine.
RESULTS: The time to remission was a median 6.9 months for patients who received phlebotomy and 6.1 months for patients treated with hydroxychloroquine treatment (6.7 and 6.5 mo for randomized patients), a difference that was not significant (log-rank, P = .06 and P = .95, respectively). The sample size was insufficient to confirm noninferiority 

2. Liver Int. 2012 Jul;32(6):880-93
Hepatitis C, porphyria cutanea tarda and liver iron: an update.
Ryan Caballes F, Sendi H, Bonkovsky HL
The Liver-Biliary-Pancreatic Center of Carolinas Medical Center, Charlotte, NC, USA.
Abstract: Porphyria cutanea tarda (PCT) is the most common form of porphyria across the world. Unlike other forms of porphyria, which are inborn errors of metabolism, PCT is usually an acquired liver disease caused by exogenous factors, chief among which are excess alcohol intake, iron overload, chronic hepatitis C, oestrogen therapy and cigarette smoking. The pathogenesis of PCT is complex and varied, but hereditary or acquired factors that lead to hepatic iron loading and increased oxidative stress are of central importance. Iron loading is usually only mild or moderate in degree [less than that associated with full-blown haemochromatosis (HFE)] and is usually acquired and/or mutations in HFE. Among acquired factors are excessive alcohol intake and chronic hepatitis C infection, which, like mutations in HFE, decrease hepcidin production by hepatocytes. The decrease in hepcidin leads to increased iron absorption from the gut. In the liver, iron loading and increased oxidative stress leads to the formation of non-porphyrin inhibitor(s) of uroporphyrinogen decarboxylase and to oxidation of porphyrinogens to porphyrins. The treatment of choice of active PCT is iron reduction by phlebotomy and maintenance of a mildly iron-reduced state without anaemia. Low-dose antimalarials (cinchona alkaloids) are also useful as additional therapy or as alternative therapy for active PCT in those without haemochromatosis or chronic hepatitis C. In this review, we provide an update of PCT with special emphasis upon the important role often played by the hepatitis C virus.
 

0 comments:

Post a Comment