1102 Letters to the Editor 6 Schiødt I, Dunn E, Fischer TK et al. Fatal rupture of the spleen caused by infiltration of T-cell lymphoma. Ann Hematol 2000; 79:158–60. 7 Bennett SR, Creer JP, Stein RS et al. Death due to splenic rupture in suppressor cell mycosis fungoides: a case report. Am J Clin Pathol 1984; 82:104–9. 8 Nores M, Phillips EH, Morgenstern L, Hiatt JR. The clinical spectrum of splenic infarction. Am Surg 1998; 64:182–8.

frequently observed mutation (Thr328Lys) has been suggested to increase activity of FXII, which in turn may trigger excess formation of bradykinin and eventually oedema.6 FXII Thr328Lys has been reported in patients of German, French, Australian, Canadian/Italian, British, Spanish and Moroccan origin. The presence of the mutation in other parts of the world has remained unclear. The clinical phenotype of HAE with normal C1-INH was recently reported in three patients from Brazil.8 In the present study, we sought the genetic defect in a so far unreported large family of Brazilian origin (Fig. 1) with 12 female patients with a clinical diagnosis of HAE. The index case is a 40-year-old female patient (Fig. 1, individual III:9) who developed her first symptoms at the age of 15. The patient was tested and found to have normal C1-INH function, and the phenotype nC1INH-HAE was established. Oral contraceptives, ovulation and menses worsened her symptoms. Oedema affected her face and extremities, and she experienced headache and abdominal pain after using medication. Facial oedema is often accompanied by mood disturbances (anxiety or depression), tiredness and headache. The index case had two pregnancies with improvement of the symptoms during those periods. After the age of 35 years, oedema affected her upper respiratory airways, requiring hospitalization in four instances. The last attack initiated with severe abdominal pain, evolving to laryngeal and uvula oedema so that uvulectomy was performed. The correct diagnosis was made when the patient was 38 years old. Oral contraceptives were suspended, and tranexamic acid was given as a prophylactic regimen. Since then, her attacks have been less severe but still occur frequently. Additional triggering factors were stress and food ingredients (pepper and strawberries), with mechanisms not clearly defined. A sister of the index case (Fig. 1; III:12) has infrequent facial and abdominal oedema caused by trauma and oral contraceptives. Their mother (Fig. 1, II:11) has had mild symptoms since the age of 16. She takes angiotensin converting enzyme (ACE) inhibitors as antihypertensive medication although ACE interferes with bradykinin metabolism. Individual II:9 (Fig. 1) presented with her first symptoms at age 49

Funding sources: none. Conflicts of interest: none declared.

First report of a FXII gene mutation in a Brazilian family with hereditary angio-oedema with normal C1 inhibitor DOI: 10.1111/bjd.13791 DEAR EDITOR, Hereditary angio-oedema [HAE (MIM #106100)] is an autosomal dominant condition characterized by recurrent swellings of the skin, the gastrointestinal and laryngeal tracts and the inner organs. Frequent complications are potentially life-threatening swellings of the tongue, pharynx and larynx that can result in asphyxiation if not treated. The most common forms of HAE with C1-inhibitor deficiency are caused by mutations in the SERPING1 [serine peptidase inhibitor, clade G (C1 inhibitor), member 1] gene.1 Such mutations lead to functional deficiency of C1-esterase inhibitor (C1-INH), resulting in excessive contact system mediated formation of the peptide bradykinin, which increases vascular permeability thereby leading to angio-oedema.2 At least one other HAE type exists which does not show mutations in SERPING1 and affects women almost exclusively.3–5 Elevated oestrogen levels often appear to trigger swelling episodes. We and others identified disease-causing missense mutations (Thr328Lys, Thr328Arg) in the blood coagulation factor XII (FXII, Hageman factor).6,7 The most

I II III

1 1

2

3

5

4

6

2 7

8

9

+/– 1

2

3

4

5

6

+/–

11

10

12

+/– 7

8

9

+/–

10 11 12

+/– +/+ +/+

14

13

13 14 15

+/–

+/+

15/16

2

3

17-19 20

21 22

+/–

23

+/–

16 17 18

+/+

Fig 1. Pedigree of a Brazilian family with hereditary angio-oedema with normal C1-esterase inhibitor. Circles denote women, squares denote men. Black symbols indicate that the individual is affected with hereditary angio-oedema with normal C1-INH (FXII-HAE). Dashed individuals are deceased. For those individuals, where DNA was available, we tested for the presence of the disease-causing mutation (c.1032C->A). (+/ ) indicates carrier of the mutation (genotype at c.1032: C/A), (+/+) indicates an individual homozygous for the wild-type allele (genotype at c.1032: C/C). British Journal of Dermatology (2015) 173, pp1095–1111

© 2015 British Association of Dermatologists

Letters to the Editor

1103

French family

Brazilian family II:11 * rs2731676 rs2252316 rs2252317 SNP_5‘reg SNP_Int2_a SNP_Int2_b SNP_Int2_c c.1032C>A SNP_Int9 SNP_Int10 rs1801020

A C A T T A C C T C

G C A T T A A C T C

III:9

rs2731676 rs2252316 rs2252317 SNP_5‘reg SNP_Int2_a SNP_Int2_b SNP_Int2_c c.1032C>A SNP_Int9 SNP_Int10 rs1801020

A T C C T A C C T C

-

A T C C T A C C T C

G C A T T A C C T C

A C A C T T A A C T A

A T C C T T A C C T A

A C A C T T A C C T A

A C A C C T A C T C A

III:10

A T C C T A C C T C

A C A T T A A C T C

A C A C T T A A C T A

A T C C T T A C C T A

* No DNA available, haplotype reconstructed

Fig 2. Haplotype analysis in a representative part of the Brazilian pedigree with HAE with normal C1INH compared with a parent–offspring trio derived from an affected French family (as described by Cichon et al.6). From the Brazilian family, individuals II:1, III:9 and III:10 were genotyped using 10 single nucleotide polymorphisms covering the complete genomic region of the FXII gene plus the disease-causing mutation (c.1032C->A). All affected individuals in both families share the same core haplotype (in red) which is compatible with the hypothesis that the mutation goes back to a common founder.

after hormone replacement therapy: her face (mouth and tongue) and abdomen were affected. Laparotomy was performed due to the abdominal attack. Her daughter (Fig. 1; III:6) developed facial and abdominal oedema at the age of 19. Individuals II:22 and II:23 are dizygotic twins; one developed sporadic abdominal distension at the age of 25 years. The other developed facial and laryngeal oedema with abdominal distension at the age of 35 years, initially triggered by pregnancy. Her daughter (Fig. 1, III:17) has abdominal pain associated with her menstrual cycle. Individual II:13 manifested the disease at the age of 30 years due to trauma. Given that only women were affected and that disease symptoms were often triggered by situations of high oestrogen levels, we speculated about a mutation in the FXII gene. We sequenced the coding sequence (14 exons) and exon/intron boundaries of the FXII gene6 and identified the known 1032C>A (resulting in Thr328Lys) mutation in all eight affected women who were available for testing (Fig. 1). Haplotype analysis of the genomic region around the FXII gene was performed as described previously6 and revealed that the haplotype bearing the mutation is identical to the one reported in European families (Fig. 2). To our knowledge, this is the first report of the presence of the FXII gene mutation (Thr328Lys) in South America. © 2015 British Association of Dermatologists

Haplotype analysis suggests that the mutation originates from Europe (genetic drift following a founder event) and does not represent an independent mutational event. In general, the very narrow mutational spectrum in the FXII gene leading to FXII-HAE (i.e. hereditary angio-oedema with normal C1-INH and confirmed mutation in the F12 gene) is quite striking (compared with the number of SERPING1 mutations in HAE with C1-INH deficiency). One plausible explanation is that mutations in the FXII gene must lead to functional changes in the transcribed FXII protein that result in increased bradykinin formation and the oedema symptoms. Only mutations at a few defined positions in the gene possibly cause such an effect and presumably occur very rarely. Further work is necessary to understand the pathophysiological mechanism mediated by the few known FXII mutations. More studies are also needed to get a clearer picture of the distribution of FXII mutations worldwide and to what extent they contribute to the heterogeneous group of HAE with normal C1-INH.

Acknowledgments This work was supported by the ERA-Net E-RARE-1 research programme (S.C., M.M.N.) within the framework of the British Journal of Dermatology (2015) 173, pp1095–1111

1104 Letters to the Editor

project ‘Genetics, Pathophysiology, and Therapy of Hereditary Angioedema Type III’. Specific laboratory analysis of C1-INH was supported by ‘Shire Research Program’. Further, we are thankful to the biologist Itatiana Ferreira Rodarte for helping with DNA extraction and the nurse Quezia Priscila Cavalcante Belomo for sample collection. 1

1,2

C. STIEBER Institute of Human Genetics and Department of Genomics, Life & Brain A.S. GRUMACH3,4 Center, University of Bonn, Germany E. CORDEIRO4 3 Outpatient Group of Recurrent Infections R . N . C O N S T A N T I N O - S I L V A 4 and 4Laboratory of Clinical Immunology, S. BARTH1,2 Center of Research, Faculty of Medicine P. HOFFMANN1,2,5 ABC, S~ao Paulo, Brazil J.B. PESQUERO6 5 Division of Medical Genetics, Department of T . R E N N E7 , 8 Biomedicine, University of Basel, Switzerland M . M . N O€ T H E N 1 , 2 6 Department of Biophysics, Federal S. CICHON1,2,5 University of S~ao Paulo, S~ao Paulo, Brazil 7 Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden 8 Department of Clinical Chemistry/Central Laboratories, University Medical Center Hamburg-Eppendorf, Hamburg, Germany Correspondence: Sven Cichon. E-mail: [email protected] 2

C.S. and A.S.G. contributed equally to this work.

References 1 Roche O, Blanch A, Duponchel C et al. Hereditary angioedema: the mutation spectrum of SERPING1/C1INH in a large Spanish cohort. Hum Mutat 2005; 26:135–44. 2 Oschatz C, Maas C, Lecher B et al. Mast cells increase vascular permeability by heparin-initiated bradykinin formation in vivo. Immunity 2011; 34:258–68. 3 Bork K, Barnstedt SE, Koch P et al. Hereditary angioedema with normal C1-inhibitor activity in women. Lancet 2000; 356:213–17. 4 Binkley KE, Davis A 3rd. Clinical, biochemical, and genetic characterization of a novel estrogen-dependent inherited form of angioedema. J Allergy Clin Immunol 2000; 106:546–50. 5 Martin L, Degenne D, Toutain A et al. Hereditary angioedema type III: an additional French pedigree with autosomal dominant transmission. J Allergy Clin Immunol 2001; 107:747–8. 6 Cichon S, Martin L, Hennies HC et al. Increased activity of coagulation factor XII (Hageman factor) causes hereditary angioedema type III. Am J Hum Genet 2006; 79:1098–104. 7 Dewald G, Bork K. Missense mutations in the coagulation factor XII (Hageman factor) gene in hereditary angioedema with normal C1 inhibitor. Biochem Biophys Res Commun 2006; 343:1286–9. 8 Miranda AR, Ue APF, Sabbag DV et al. Hereditary angioedema type III (estrogen-dependent) report of three cases and literature review. An Bras Dermatol 2013; 88:578–84. Funding sources: none. Conflicts of interest: none declared.

British Journal of Dermatology (2015) 173, pp1095–1111

Place your bet and show us your hand DOI: 10.1111/bjd.13944 DEAR EDITOR, Although not simple to do, most clinical trials are simple in concept. Trials start by asking a question such as ‘In people with invasive cutaneous melanoma, is wide excision followed by sentinel node biopsy and immediate lymphadenectomy for nodal metastases better than wide excision followed by nodal observation?’, as was done in the Multicenter Selective Lymphadenectomy Trial (MSLT)-1 study.1 Critical to conducting such a trial is the need for the study team to ‘place its bet’ by selecting the primary outcome on which the trial’s ‘success’ will be judged, and then to ‘show its hand’ for that primary outcome measure by reporting it prominently in the key publication abstract and text.2 The declared primary outcome in the MSLT-1 trial registration document is ‘To determine whether wide excision of the primary with intraoperative lymphatic mapping (LM) followed by selective lymphadenectomy will effectively prolong overall survival compared to wide excision of the primary melanoma alone. [Time Frame: 10 years ]’.3 Despite this clear statement, the final 10-year report fails to mention overall survival in the abstract or anywhere else in the article or supplementary material. Sladden et al. try to help readers by attempting to derive overall survival data from the study report using an intention-to-treat analysis, which suggested no overall survival for sentinel biopsy plus selective lymphadenectomy.4 Instead of reporting the planned primary outcome, the authors chose to highlight melanoma-specific survival, which they describe as the primary outcome in their 10-year report. Melanoma-specific survival also showed no significant treatment benefit in the predefined study population. A trial like MSLT-1 is unlikely to be repeated. It is very disappointing to witness how such a capable team has chosen to avoid presenting the planned primary outcome measure, the reasons for which remain a mystery. Undoubtedly, the trial will be frequently cited, both for its clinical findings and as a teaching example of selective reporting outcome bias.5 Department of Dermatology, Queen’s Medical Centre, Nottingham, U.K. E-mail: [email protected]

H.C. WILLIAMS

References 1 Morton DL, Thompson JF, Cochran AJ et al.; MSLT Group. Final trial report of sentinel-node biopsy versus nodal observation in melanoma. N Engl J Med 2014; 370:599–609. 2 Williams HC, Gilchrest B. Clinical trials submitted to the JID: place your bet and show us your hand. J Invest Dermatol 2015; 135:325–7. 3 ClinicalTrials.gov. Multicenter Selective Lymphadenectomy Trial (MSLT). Available at: https://clinicaltrials.gov/ct2/show/NCT0027 5496 (last accessed 18 August 2015). 4 Sladden M, Zagarella S, Popescu C, Bigby M. No survival benefit for patients with melanoma undergoing sentinel lymph node biopsy:

© 2015 British Association of Dermatologists