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Renal manifestations of hereditary angioedema
CORRESPONDENCE
muscle weakness and increased levels of serum aldolase" and that muscle inflammation "would also explain the elevated levels of aldolase." These two statements are certainly true. Aldolase, a c o m p o n e n t of t h e g l y c o l y t i c pathway, is present in skeletal myocyte8. However, it is imporSubmitted August 8, 1990, and accepted October tant to note that aldolase is not a 1, 1990 m u s c l e - s p e c i f i c enzyme. T h e presence of an elevated serum alThe Reply: This is in response to the letterby dolase level cannot in and of itself Hory and Blanc concerning our re- be used to specifically diagnose cent review of hereditary angioe- myositis. Aldolase is present in dema We are in agreement with many other cells of the body, intheir report [1] of the possible as- cluding hepatocytes and erythrosociation of HAE with autoim- cytes. Although the specific acmune diseases, especially those in- tivity (U/g of tissue) is lower in volving the kidney. We would erythrocytes than in muscle [2], again emphasize, as we did in our depending upon the briskness of review, that the cause of this rela- hemolysis and plasma clearance tionship is still debated and re- of the enzyme, serum levels may quires further careful observation increase. The enzyme creatine and studies. In another case re- phosphokinase (CPK) is a far more port, they described a patient with specific enzyme to demonstrate H A E who developed Guillain- muscle involvement in inflAmmaBarr~ syndrome following danazol tory disorders, once a brain source therapy [2]. We apologize for the has been ruled out. Unless the CPK om;asion of this article in our re- was also elevated in the case under view. We sincerely thank them for discussion, I would suggest that the elevated serum aldolase activity in their interesting contributions. TOMMY C. SIM, M.D. this particular case could be due to J. ANDREW GRANT, M.D. a non-muscle source. The University of Texas Medical These comments should in no Branch Hospitals Galveston, Texas way detract from the diagnosis properly made of T T P in associa1. Hory B, Haultier JJ. Glomerulonephritis and hereditary angioedema: report of two cases. Clin tion with an underlying connecNephrol 1989; 31: 259-63. tive tissue disorder. T h e y are 2. Hory B, Blanc D, Boillot A, Panouse-Perrin J. Guilonly to point out the fact that an lain-Barr~ syndrome following danazol and corticoelevated aldolase level, in the absteroid therapy for hereditary angioedema. Am J Med 1985; 79: 111-4. sence of an elevated CPK level, cannot be used as unequivocal evidence of muscle involvement, ALDOLASE IN THE DIAGNOSIS unless necrosis of other organs or OF MYOSITIS hemolysis can be ruled out.
steroid therapy for hereditary angioedema. Am J Med 1985; 79: 111-4. 3. Hory B, Haultier JJ. Glomerulonephritis and hereditary angioedema: report of two cases. Clin Nephrol 1989; 31: 259-63. 4. Fretwell MD, Airman LC. Exacerbation of a lupus erythematosus-like syndrome during treatment of non-Cl-esterase inhibitor dependent angioedema with danazol. J Allergy Clin Immuno11982; 69: 30610.
To the Editor:
In the excellent discussion of thrombotic thrombocytopenic purpura (TTP) as part of the Clinicopathologic Conference in the August 1990 issue [1], statements regarding the use of aldolase in the diagnosis of myositis need clarification. It was'suggested that the patient had muscle involvement "as judged by both ££9
May 1991
IRON REPLETION AS A CONTRIBUTION TO ERYTHROPOIETIN TREATMENT OF ANEMIA IN RHEUMATOID ARTHRITIS To the Editor:
We were very much interested in the recent report by Pincus et al [1] on the treatment of anemia in r h e u m a t o i d arthritis (RA). A great deal of research has been carried out on the pathogenesis of anemia of chronic disease (ACD) in RA. Various factors have been studied, such as decreased bone marrow iron availability, impaired iron absorption, and cytokines like tumor necrosis factor-~ and interleukins [2-4]. Indeed, the role of erythropoietin (EPO) responsiveness has been the subject of several recent studies [5,6]. M o s t p r o b a b l y , t h e E P O response to anemia in RA is relatively impaired, although decreased bone marrow sensitivity might be important as well [6]. All these studies dealt with the possible role of EPO response in ACD, but evidence can only be confirmed by treatment with recombinant h u m a n E P O (rHuEPO). Some reports already have been published [7,8]. Because of the theoretic aspects of studies on EPO response in anemia of RA, the study by Pincu8 et al [1] deserves major attention. The authors observed that all their patients had an increase in t h e h e m o g l o b i n level a f t e r 8 weeks of treatment with rHuEPO, which is encouraging. We think the EPO treatment schedule and the description of relevant parameters and follow-up BRIAN F. MANDELL, M.D., Ph.D. were carefully documented. In The Graduate Hospital their discussion, the a u t h o r s University of Pennsylvania School of Medicine state that a concern of the study Philadelphia, Pennsylvania involved the fact that some patients were iron-deficient` If the 1.Clinicopathologic Conference. Melena, anemia, criterion of an iron level, i.e., ferrenal insufficiency, and respiratory failure in a 47ritin level, lower than 60 ug/L year-old woman. Am J Med 1990; 89: 223-8. cited by the authors is used, anal2. Newsholme EA, Start C. Regulation in metabolism. New York: John Wiley and Sons, 1973: 98. ysis of the baseline characteristics of their patients shows that Submitted October 22, 1990, and accepted November 19, 1990 11 of 17 (65%; Table II) were iron-
Tha American Journal of Medicine
Volume 90
muscle weakness and increased levels of serum aldolase" and that muscle inflammation "would also explain the elevated levels of aldolase." These two statements are certainly true. Aldolase, a c o m p o n e n t of t h e g l y c o l y t i c pathway, is present in skeletal myocyte8. However, it is imporSubmitted August 8, 1990, and accepted October tant to note that aldolase is not a 1, 1990 m u s c l e - s p e c i f i c enzyme. T h e presence of an elevated serum alThe Reply: This is in response to the letterby dolase level cannot in and of itself Hory and Blanc concerning our re- be used to specifically diagnose cent review of hereditary angioe- myositis. Aldolase is present in dema We are in agreement with many other cells of the body, intheir report [1] of the possible as- cluding hepatocytes and erythrosociation of HAE with autoim- cytes. Although the specific acmune diseases, especially those in- tivity (U/g of tissue) is lower in volving the kidney. We would erythrocytes than in muscle [2], again emphasize, as we did in our depending upon the briskness of review, that the cause of this rela- hemolysis and plasma clearance tionship is still debated and re- of the enzyme, serum levels may quires further careful observation increase. The enzyme creatine and studies. In another case re- phosphokinase (CPK) is a far more port, they described a patient with specific enzyme to demonstrate H A E who developed Guillain- muscle involvement in inflAmmaBarr~ syndrome following danazol tory disorders, once a brain source therapy [2]. We apologize for the has been ruled out. Unless the CPK om;asion of this article in our re- was also elevated in the case under view. We sincerely thank them for discussion, I would suggest that the elevated serum aldolase activity in their interesting contributions. TOMMY C. SIM, M.D. this particular case could be due to J. ANDREW GRANT, M.D. a non-muscle source. The University of Texas Medical These comments should in no Branch Hospitals Galveston, Texas way detract from the diagnosis properly made of T T P in associa1. Hory B, Haultier JJ. Glomerulonephritis and hereditary angioedema: report of two cases. Clin tion with an underlying connecNephrol 1989; 31: 259-63. tive tissue disorder. T h e y are 2. Hory B, Blanc D, Boillot A, Panouse-Perrin J. Guilonly to point out the fact that an lain-Barr~ syndrome following danazol and corticoelevated aldolase level, in the absteroid therapy for hereditary angioedema. Am J Med 1985; 79: 111-4. sence of an elevated CPK level, cannot be used as unequivocal evidence of muscle involvement, ALDOLASE IN THE DIAGNOSIS unless necrosis of other organs or OF MYOSITIS hemolysis can be ruled out.
steroid therapy for hereditary angioedema. Am J Med 1985; 79: 111-4. 3. Hory B, Haultier JJ. Glomerulonephritis and hereditary angioedema: report of two cases. Clin Nephrol 1989; 31: 259-63. 4. Fretwell MD, Airman LC. Exacerbation of a lupus erythematosus-like syndrome during treatment of non-Cl-esterase inhibitor dependent angioedema with danazol. J Allergy Clin Immuno11982; 69: 30610.
To the Editor:
In the excellent discussion of thrombotic thrombocytopenic purpura (TTP) as part of the Clinicopathologic Conference in the August 1990 issue [1], statements regarding the use of aldolase in the diagnosis of myositis need clarification. It was'suggested that the patient had muscle involvement "as judged by both ££9
May 1991
IRON REPLETION AS A CONTRIBUTION TO ERYTHROPOIETIN TREATMENT OF ANEMIA IN RHEUMATOID ARTHRITIS To the Editor:
We were very much interested in the recent report by Pincus et al [1] on the treatment of anemia in r h e u m a t o i d arthritis (RA). A great deal of research has been carried out on the pathogenesis of anemia of chronic disease (ACD) in RA. Various factors have been studied, such as decreased bone marrow iron availability, impaired iron absorption, and cytokines like tumor necrosis factor-~ and interleukins [2-4]. Indeed, the role of erythropoietin (EPO) responsiveness has been the subject of several recent studies [5,6]. M o s t p r o b a b l y , t h e E P O response to anemia in RA is relatively impaired, although decreased bone marrow sensitivity might be important as well [6]. All these studies dealt with the possible role of EPO response in ACD, but evidence can only be confirmed by treatment with recombinant h u m a n E P O (rHuEPO). Some reports already have been published [7,8]. Because of the theoretic aspects of studies on EPO response in anemia of RA, the study by Pincu8 et al [1] deserves major attention. The authors observed that all their patients had an increase in t h e h e m o g l o b i n level a f t e r 8 weeks of treatment with rHuEPO, which is encouraging. We think the EPO treatment schedule and the description of relevant parameters and follow-up BRIAN F. MANDELL, M.D., Ph.D. were carefully documented. In The Graduate Hospital their discussion, the a u t h o r s University of Pennsylvania School of Medicine state that a concern of the study Philadelphia, Pennsylvania involved the fact that some patients were iron-deficient` If the 1.Clinicopathologic Conference. Melena, anemia, criterion of an iron level, i.e., ferrenal insufficiency, and respiratory failure in a 47ritin level, lower than 60 ug/L year-old woman. Am J Med 1990; 89: 223-8. cited by the authors is used, anal2. Newsholme EA, Start C. Regulation in metabolism. New York: John Wiley and Sons, 1973: 98. ysis of the baseline characteristics of their patients shows that Submitted October 22, 1990, and accepted November 19, 1990 11 of 17 (65%; Table II) were iron-
Tha American Journal of Medicine
Volume 90