- Email: [email protected]
Interaction of thyrotropin and thyroid-stimulating antibodies with recombinant extracellular region of human TSH receptor
193
neutropenic (haemoglobin 10-7 g/dl, white blood cells 74 x 109/1, platelets 188 x 109/1). Stool specimens were cultured and intravenous fluids were started. Diarrhoea continued for a further 4 days, when Clostridium difficile toxin was detected in stool. She was therefore started on oral vancomycin 125 mg four times daily and diarrhoea stopped within 48 hours. Pseudomembranous colitis is an acute colonic infection caused by C difficile that usually occurs as a complication of antibiotic therapy and rarely develops spontaneously in healthy individuals. C difficile colitis has been reported in patients undergoing intensive chemotherapy usually for acute leukaemia, and in whom antibiotics had been given.’ There is only one previous report of pseudomembranous colitis after chemotherapy without previous antibiotic administration.2 was not
50% of patients on CMF report diarrhoea although only 7% have severe diarrhoea;’ however, it is rarely longlasting. Our findings emphasise the importance of investigating the aetiology of longlasting diarrhoea in patients receiving chemotherapy since they may have an increased susceptibility to pseudomembranous colitis. Department of Medicine,
Royal Marsden Hospital,
T. J. IVESON
London SW3 6JJ, UK
A. CHAN
GM, Luna M, Valdivieso M, et al Necrotizing colitis in patients with cancer. Am J Med 1979; 67: 646-55. 2. Fainstein V, Bodey GP, Fekety R. Relapsing pseudomembranous colitis associated with cancer chemotherapy J Infect Dis 1981; 143: 865. 3. Jodrell DI, Smith IE, Mansi JL, et al A randomised comparative trial of mitozantrone/methotrexate/mitomycin C (MMM) and cyclophosphamide/ methotrexate/5FU (CMF) in the treatment of advanced breast cancer. Br J Cancer 1991, 63: 794-98 1. Dosik
Fetal
haemorrhagic lesions after chorionic villous sampling
SIR,-A causal relation between chorionic villous sampling
(CVS) and limb reduction anomalies is controversial (ref 1 and subsequent correspondence, Lancet 1991; 337: 1091-92, 1422-24). Haemodynamic insult at a critical time in gestation has been proposed as a mechanism for these anomalies, but no direct evidence for this proposal exists. We have seen with embryoscopy fetal ecchymotic lesions after transvaginal CVS before termination of pregnancy at 9-5 menstrual weeks. Lesions were located on the calvarium, face (philtrum), thorax, and distal segments of the limbs (figure). The lesions became larger during 10 minutes of observation. Ultrasonography during CVS showed the development of a subchorionic haematoma. There was no family history of a haemorrhagic disorder. This fmding suggested that the trauma associated with CVS may lead to haemorrhagic fetal lesions.
Endoscopic demonstration of vessels of the fetal forehead Fetal eye is
on
left
two
haemorrhagic
(arrows).
lesions
along
To test this hypothesis we did embryoscopy before and after CVS in patients scheduled to have elective pregnancy termination between 8 and 12 weeks’. Human investigation committee approval and informed consent were obtained for all these studies. Embryoscopy was done with a ’Storz’ 27 mm 30° angle endoscope.2 CVS was done with a standard 1 5mm ’Portex’ cannula. No lesions were seen before or after CVS. We then proceeded to induce partial placental detachment and subchorionic haematoma formation with a blunt instrument (uterine sound or cervical dilator). No changes in fetal heart rate were seen during this procedure. After placental trauma, six of seven fetuses showed ecchymotic lesions on the head, face, and thorax. In one of these six, lesions were also seen along the tract of the vitelline vessels and on the yolk sac. These observations provide direct evidence that placental trauma in early pregnancy may lead to demonstrable fetal lesions. The clinical significance of these lesions and the mechanism by which they occur are unknown. Although some lesions may be unimportant, others may be the pathological basis for limb reduction anomalies and oromandibular hypogenesis reported in fetuses after CVS procedures, especially if placental trauma is extensive. Our observations probably represent the extreme of a spectrum of lesions after placental trauma. We do not believe that these lesions are the result of embryoscopy since they have not been noted in over 200 embryoscopies done in our institution during the past three years. The frequency with which these lesions occur after routine CVS is unknown. Gestational age, technique of CVS, and degree of placental trauma, as shown, for example, by the appearance of sub-chorionic haemorrhage, may be implicated. Embryoscopy affords the opportunity to study these factors under controlled conditions. RUBEN A. QUINTERO ROBERTO ROMERO MAURICE J. MAHONEY MARILYN VECCHIO Department of Obstetrics and Gynecology, HOLDEN JOANN Yale University School of Medicine, New Haven, Connecticut 06510, USA JOHN C. HOBBINS 1. Firth HV, Boyd PA, Chamberlain P, MacKenzie IZ, Lindenbaum RH, Huson SM. Severe limb abnormalities after chonon villus sampling at 56-66 days’ gestation. Lancet 1991; 337: 782-83. 2. Cullen MT, Reece EA, Whetham J, Hobbins JC Embryoscopy. description and utility of a new technique Am JObstet Gynecol 1990; 162: 82-86.
Interaction
of thyrotropin and thyroid-stimulating antibodies with recombinant extracellular region of human TSH receptor SIR,-The human thyrotropin (TSH) receptor (hTSHr) is one of the commonest targets of autoimmune disease, but its structure was unknown until its cDNA was cloned. The predicted aminoacid sequence suggests a large extracellular region, seven transmembrane regions, and a cytoplasmic tail; TSH is presumed to bind to the extracellular region. Autoantibodies to hTSHr are very heterogeneous. 2 years after the receptor was cloned, the hTSHr domains that are important in interacting with these antibodies remain uncertain. Several groups have investigated the effect of synthetic peptides corresponding to the predicted sequence of various regions, and of antibodies raised against these peptides, on autoantibody and TSH binding and on functional stimulation of thyroid cells, but, unfortunately, no clear and consistent answers have been obtained (eg, refs 1 and 2). Indeed, Libert and colleagues3 have produced compelling evidence that linear sequences (up to 70 aminoacids) are not sufficient for autoantibody binding. Thus, it is clear that the difficulties in developing useful assays for the detection and measurement of hTSHr autoantibodies will not be solved by use of a few synthetic peptides. We therefore sought to produce substantial quantities of a recombinant protein consisting of the entire extracellular region; to facilitate correct glycosylation and other post-translational processing, we used a eukaryotic system. A stop codon was introduced into hTSHr cDNA just before the first predicted transmembrane region (residue 417) and this was expressed in Chinese hamster ovary (CHO) cells with the novel amplifiable
194
3. Libert F,
Ludgate M, Dinsart C, Vassart G. Thyroperoxidase, but not the thyrotropin
receptor, contains sequential epitopes recognised by autoantibodies m recombinant peptides expressed in the pUEX vector.J Clin Endocrinol Metab 1991; 73: 857-60. 4. Harfst E, Johnstone AP, Gout I, Taylor AH, Waterfield MD, Nussey SS. The use of the amplifiable high-expression vector pEE14 to study the interactions of autoanubodies with recombinant human thyrotrophm receptor. Mol Cell Endocrinol (in press). 5. Xie Y-B, Wang H, Segaloff DL. Extracellular domain of lutropin/choriogonadotropin receptor expressed in transfected cells binds choriogonadotropin with high affinity. J Biol Chem 1990; 265: 21411-14. 6. Dirmikis S, Munro DS. Studies on the binding activity for the long-acting thyroid stimulator. J Endocrinol 1973; 58: 577-90. 7. Adlkofer F, Kotulla P, Schleusener H. Binding of thyrotrophin to low molecular weight fragments of human thyroid membranes. Acta Endocrinol (Copenh) 1980, 94: 58-63.
Influenza vaccination in asthma Inhibition of adenylate cyclase activity stimulated by autoantisera or (B) TSH.
(A)
Inhibition of adenylate cyclase activity in a CHO clone expressing full-length hTSHR protein, by homogenates of non-transfected CHO cells (CHO), two individual clones which express full length hTSHr (FL and FL+; about 30 000 and 80 000 TSH binding sites per cell, respectively), and a clone expressing even higher levels of the hTSHRR extracellular region (EX). Value for 100% inhibition is taken as cyclic AMP concentrations in assay buffer alone, and 0% is value for TSH or antisera in absence of cell homogenates n = 11-18, means and SEM (vertical bars) shown
high-expression pEE14 system (Celltech), as we have already described for full-length hTSHr (FL-hTSHr).4 The resultant protein could be seen, by immunoprecipitation and immunoblotting, to be a glycoprotein of about 55 000 molecular weight. The binding functions of this product were then investigated by its ability to absorb cAMP stimulating activity from TSH and autoantibodies. Cells containing recombinant protein were freeze-thawed and sonicated in hypotonic buffer containing protease inhibitors (106 cells/ml) and incubated with either bovine TSH (’Thyrotropin’, Armour, at a fmal concentration of 50 RU/ml) or untreated Graves’ serum samples (final dilution 1 in 10) for 30 min at 37°C; the concentrations of agonist were chosen to give about half-maximum stimulation of cAMP production. After centrifugation, the supernatant (250 µl) was tested for its cAMPstimulating activity as describedexcept that intracellular cAMP was measured after washing of the cells and extraction with 70% ethanol. The results (figure) clearly show that the external hTSHr domain was potent in reducing the activity of autoantibodies, but had very little effect on the activity of TSH. By contrast, cells containing full-length hTSHr, especially after amplification of expression, were equipotent in absorbing both TSH and autoantibodies (figure). These results are surprising in view of the predictions from the cDNA sequence; the similar lutropin (LH)/chorionic gonadotropin receptor external region binds labelled chorionic gonadotropin with high affinityHowever, our data are compatible with results obtained from early studies6,7 on the absorption of autoantibodies by human thyroid membranes; mechanical disruption of these membranes caused the solubilisation of a part of the hTSHr that retained the capacity to bind antibodies but which had a much reduced affinity for TSH. This had a sedimentation coefficient of 4S (about 50 000 molecular weight-the so-called 4S-LAA) suggesting that it is a large part of the hTSHr external domain fractured during preparation at or near the membrane insertion. We conclude that the hTSHr extracellular region contains epitopes for stimulating autoantibodies but is insufficient to constitute the high-affinity TSH binding site. Division of Biochemical Medicine, St George’s Hospital Medical School, London SW17 ORE, UK
ELIZABETH HARFST A. P. JOHNSTONE S. S. NUSSEY
SIR,-A large number of people are vaccinated with influenza vaccine every winter, since the UK Chief Medical Officer recommends an annual influenza vaccination for people at special risk, especially elderly patients, those with chronic pulmonary disease, chronic heart disease, chronic renal disease, and diabetes mellitus, and those receiving immunosuppressant therapy. Influenza vaccines are of two main types, live attenuated and inactivated. The inactivated vaccine is available in two forms, split virus vaccine and surface antigen vaccine. These vaccines have many side-effects. Because asthma exacerbations can be triggered by upper-respiratory-tract infections, a large number of asthmatics are vaccinated against influenza each year, but a viral aetiology has not been confirmed in more than 20% of such exacerbations in adults. Influenza vaccination is known to increase bronchial reactivity and cause exacerbations of asthma. 2,3 Some of our patients had exacerbations of asthma after such vaccination and three were admitted, one of whom needed assisted ventilation in the intensive care unit. These cases have been reported to the Committee on Safety of Medicines. We do not recommend an annual influenza vaccine in stable asthmatics, because of the potential side-effects. Perhaps those patients whose asthma is unstable, and who had frequent exacerbations in the previous year after upper-respiratory-tract infections, should be vaccinated with sub-unit vaccine. These vaccines are prepared by separating surface antigens from the core virus by selective solubilisation,4have fewer side-effects, and are well tolerated by a group of moderately severe asthmatics.5 WAJAHAT U. HASSAN
1. Brewis RAL, Gibson GJ, Geddes DM. Respir Med 1990; 17: 648. 2 Dejongste JC, Degenhart HC, Neijens HJ, et al. Bronchial responsiveness and leucocyte reactivity after influenza vaccine m asthmatic patients. Eur J Respir 1984; 65: 196. 3. Oukette JJ, Reed CE. Increased response of asthmatic subjects to methacholine after influenza vaccine. J Allergy 1965; 36: 558-63. 4. Backmayer H. Selective solubilisation of haemagglutinin and neuroaminidase from influenza viruses. Intervirology 1975; 5: 260-68. 5. Albazzaz MK, Harvey JE, Grilli EA, Caul EO, Roome AP. Subunit influenza vaccination in adults with asthma: effects on clinical state, airway reactivity and antibody response. Br Med J 1987; 294: 1196.
Tegernsee giant p
SIR,-Dr Nerlich (Oct 5, p 886) and Dr Schwindinger (Dec 7, 1454) and their colleagues speculate on the possible coexistence of
juvenile gigantism and polyostotic fibrous dysplasia in the Tegemsee giant, but are unaware that this association has already been reported.1 The first of the two patients described was a boy born in Nottingham in 1930, whom I saw in Manchester Royal Infirmary in 1954, and who was still alive, though severely disabled by bone disease, in the late 1960s. Department
1 Ohmon M, Endo T, Onaya T. Development of chicken antibodies toward the human thyrotropin receptor peptides and their bioactivities. Biochem Biophys Res Commun
1991; 174: 399-403. 2. Kosugi S, Ban T, Akamizu T, Kohn LD. Site-directed mutagenesis of a portion of the extracellular domain of the rat thyrotropin receptor important m autoimmune thyroid disease and nonhomologous with gonadotropm receptors. Relationship of functional and immunogenic domains J Biol Chem 1991; 266: 19413-18.
ALLAN F. HENDERSON NIALL P. KEANEY
Royal Infirmary, Sunderland SR2 7JE, UK
of Medicine,
Rayne Institute, University College and Middlesex School of Medicine, London WC1 E 6JJ, UK 1. Falconer
OLIVER WRONG
MA, Cope CL. Fibrous dysplasia of bone with endocrine disorders pigmentation. Q J Med 1942; 11: 121-54.
cutaneous
and
neutropenic (haemoglobin 10-7 g/dl, white blood cells 74 x 109/1, platelets 188 x 109/1). Stool specimens were cultured and intravenous fluids were started. Diarrhoea continued for a further 4 days, when Clostridium difficile toxin was detected in stool. She was therefore started on oral vancomycin 125 mg four times daily and diarrhoea stopped within 48 hours. Pseudomembranous colitis is an acute colonic infection caused by C difficile that usually occurs as a complication of antibiotic therapy and rarely develops spontaneously in healthy individuals. C difficile colitis has been reported in patients undergoing intensive chemotherapy usually for acute leukaemia, and in whom antibiotics had been given.’ There is only one previous report of pseudomembranous colitis after chemotherapy without previous antibiotic administration.2 was not
50% of patients on CMF report diarrhoea although only 7% have severe diarrhoea;’ however, it is rarely longlasting. Our findings emphasise the importance of investigating the aetiology of longlasting diarrhoea in patients receiving chemotherapy since they may have an increased susceptibility to pseudomembranous colitis. Department of Medicine,
Royal Marsden Hospital,
T. J. IVESON
London SW3 6JJ, UK
A. CHAN
GM, Luna M, Valdivieso M, et al Necrotizing colitis in patients with cancer. Am J Med 1979; 67: 646-55. 2. Fainstein V, Bodey GP, Fekety R. Relapsing pseudomembranous colitis associated with cancer chemotherapy J Infect Dis 1981; 143: 865. 3. Jodrell DI, Smith IE, Mansi JL, et al A randomised comparative trial of mitozantrone/methotrexate/mitomycin C (MMM) and cyclophosphamide/ methotrexate/5FU (CMF) in the treatment of advanced breast cancer. Br J Cancer 1991, 63: 794-98 1. Dosik
Fetal
haemorrhagic lesions after chorionic villous sampling
SIR,-A causal relation between chorionic villous sampling
(CVS) and limb reduction anomalies is controversial (ref 1 and subsequent correspondence, Lancet 1991; 337: 1091-92, 1422-24). Haemodynamic insult at a critical time in gestation has been proposed as a mechanism for these anomalies, but no direct evidence for this proposal exists. We have seen with embryoscopy fetal ecchymotic lesions after transvaginal CVS before termination of pregnancy at 9-5 menstrual weeks. Lesions were located on the calvarium, face (philtrum), thorax, and distal segments of the limbs (figure). The lesions became larger during 10 minutes of observation. Ultrasonography during CVS showed the development of a subchorionic haematoma. There was no family history of a haemorrhagic disorder. This fmding suggested that the trauma associated with CVS may lead to haemorrhagic fetal lesions.
Endoscopic demonstration of vessels of the fetal forehead Fetal eye is
on
left
two
haemorrhagic
(arrows).
lesions
along
To test this hypothesis we did embryoscopy before and after CVS in patients scheduled to have elective pregnancy termination between 8 and 12 weeks’. Human investigation committee approval and informed consent were obtained for all these studies. Embryoscopy was done with a ’Storz’ 27 mm 30° angle endoscope.2 CVS was done with a standard 1 5mm ’Portex’ cannula. No lesions were seen before or after CVS. We then proceeded to induce partial placental detachment and subchorionic haematoma formation with a blunt instrument (uterine sound or cervical dilator). No changes in fetal heart rate were seen during this procedure. After placental trauma, six of seven fetuses showed ecchymotic lesions on the head, face, and thorax. In one of these six, lesions were also seen along the tract of the vitelline vessels and on the yolk sac. These observations provide direct evidence that placental trauma in early pregnancy may lead to demonstrable fetal lesions. The clinical significance of these lesions and the mechanism by which they occur are unknown. Although some lesions may be unimportant, others may be the pathological basis for limb reduction anomalies and oromandibular hypogenesis reported in fetuses after CVS procedures, especially if placental trauma is extensive. Our observations probably represent the extreme of a spectrum of lesions after placental trauma. We do not believe that these lesions are the result of embryoscopy since they have not been noted in over 200 embryoscopies done in our institution during the past three years. The frequency with which these lesions occur after routine CVS is unknown. Gestational age, technique of CVS, and degree of placental trauma, as shown, for example, by the appearance of sub-chorionic haemorrhage, may be implicated. Embryoscopy affords the opportunity to study these factors under controlled conditions. RUBEN A. QUINTERO ROBERTO ROMERO MAURICE J. MAHONEY MARILYN VECCHIO Department of Obstetrics and Gynecology, HOLDEN JOANN Yale University School of Medicine, New Haven, Connecticut 06510, USA JOHN C. HOBBINS 1. Firth HV, Boyd PA, Chamberlain P, MacKenzie IZ, Lindenbaum RH, Huson SM. Severe limb abnormalities after chonon villus sampling at 56-66 days’ gestation. Lancet 1991; 337: 782-83. 2. Cullen MT, Reece EA, Whetham J, Hobbins JC Embryoscopy. description and utility of a new technique Am JObstet Gynecol 1990; 162: 82-86.
Interaction
of thyrotropin and thyroid-stimulating antibodies with recombinant extracellular region of human TSH receptor SIR,-The human thyrotropin (TSH) receptor (hTSHr) is one of the commonest targets of autoimmune disease, but its structure was unknown until its cDNA was cloned. The predicted aminoacid sequence suggests a large extracellular region, seven transmembrane regions, and a cytoplasmic tail; TSH is presumed to bind to the extracellular region. Autoantibodies to hTSHr are very heterogeneous. 2 years after the receptor was cloned, the hTSHr domains that are important in interacting with these antibodies remain uncertain. Several groups have investigated the effect of synthetic peptides corresponding to the predicted sequence of various regions, and of antibodies raised against these peptides, on autoantibody and TSH binding and on functional stimulation of thyroid cells, but, unfortunately, no clear and consistent answers have been obtained (eg, refs 1 and 2). Indeed, Libert and colleagues3 have produced compelling evidence that linear sequences (up to 70 aminoacids) are not sufficient for autoantibody binding. Thus, it is clear that the difficulties in developing useful assays for the detection and measurement of hTSHr autoantibodies will not be solved by use of a few synthetic peptides. We therefore sought to produce substantial quantities of a recombinant protein consisting of the entire extracellular region; to facilitate correct glycosylation and other post-translational processing, we used a eukaryotic system. A stop codon was introduced into hTSHr cDNA just before the first predicted transmembrane region (residue 417) and this was expressed in Chinese hamster ovary (CHO) cells with the novel amplifiable
194
3. Libert F,
Ludgate M, Dinsart C, Vassart G. Thyroperoxidase, but not the thyrotropin
receptor, contains sequential epitopes recognised by autoantibodies m recombinant peptides expressed in the pUEX vector.J Clin Endocrinol Metab 1991; 73: 857-60. 4. Harfst E, Johnstone AP, Gout I, Taylor AH, Waterfield MD, Nussey SS. The use of the amplifiable high-expression vector pEE14 to study the interactions of autoanubodies with recombinant human thyrotrophm receptor. Mol Cell Endocrinol (in press). 5. Xie Y-B, Wang H, Segaloff DL. Extracellular domain of lutropin/choriogonadotropin receptor expressed in transfected cells binds choriogonadotropin with high affinity. J Biol Chem 1990; 265: 21411-14. 6. Dirmikis S, Munro DS. Studies on the binding activity for the long-acting thyroid stimulator. J Endocrinol 1973; 58: 577-90. 7. Adlkofer F, Kotulla P, Schleusener H. Binding of thyrotrophin to low molecular weight fragments of human thyroid membranes. Acta Endocrinol (Copenh) 1980, 94: 58-63.
Influenza vaccination in asthma Inhibition of adenylate cyclase activity stimulated by autoantisera or (B) TSH.
(A)
Inhibition of adenylate cyclase activity in a CHO clone expressing full-length hTSHR protein, by homogenates of non-transfected CHO cells (CHO), two individual clones which express full length hTSHr (FL and FL+; about 30 000 and 80 000 TSH binding sites per cell, respectively), and a clone expressing even higher levels of the hTSHRR extracellular region (EX). Value for 100% inhibition is taken as cyclic AMP concentrations in assay buffer alone, and 0% is value for TSH or antisera in absence of cell homogenates n = 11-18, means and SEM (vertical bars) shown
high-expression pEE14 system (Celltech), as we have already described for full-length hTSHr (FL-hTSHr).4 The resultant protein could be seen, by immunoprecipitation and immunoblotting, to be a glycoprotein of about 55 000 molecular weight. The binding functions of this product were then investigated by its ability to absorb cAMP stimulating activity from TSH and autoantibodies. Cells containing recombinant protein were freeze-thawed and sonicated in hypotonic buffer containing protease inhibitors (106 cells/ml) and incubated with either bovine TSH (’Thyrotropin’, Armour, at a fmal concentration of 50 RU/ml) or untreated Graves’ serum samples (final dilution 1 in 10) for 30 min at 37°C; the concentrations of agonist were chosen to give about half-maximum stimulation of cAMP production. After centrifugation, the supernatant (250 µl) was tested for its cAMPstimulating activity as describedexcept that intracellular cAMP was measured after washing of the cells and extraction with 70% ethanol. The results (figure) clearly show that the external hTSHr domain was potent in reducing the activity of autoantibodies, but had very little effect on the activity of TSH. By contrast, cells containing full-length hTSHr, especially after amplification of expression, were equipotent in absorbing both TSH and autoantibodies (figure). These results are surprising in view of the predictions from the cDNA sequence; the similar lutropin (LH)/chorionic gonadotropin receptor external region binds labelled chorionic gonadotropin with high affinityHowever, our data are compatible with results obtained from early studies6,7 on the absorption of autoantibodies by human thyroid membranes; mechanical disruption of these membranes caused the solubilisation of a part of the hTSHr that retained the capacity to bind antibodies but which had a much reduced affinity for TSH. This had a sedimentation coefficient of 4S (about 50 000 molecular weight-the so-called 4S-LAA) suggesting that it is a large part of the hTSHr external domain fractured during preparation at or near the membrane insertion. We conclude that the hTSHr extracellular region contains epitopes for stimulating autoantibodies but is insufficient to constitute the high-affinity TSH binding site. Division of Biochemical Medicine, St George’s Hospital Medical School, London SW17 ORE, UK
ELIZABETH HARFST A. P. JOHNSTONE S. S. NUSSEY
SIR,-A large number of people are vaccinated with influenza vaccine every winter, since the UK Chief Medical Officer recommends an annual influenza vaccination for people at special risk, especially elderly patients, those with chronic pulmonary disease, chronic heart disease, chronic renal disease, and diabetes mellitus, and those receiving immunosuppressant therapy. Influenza vaccines are of two main types, live attenuated and inactivated. The inactivated vaccine is available in two forms, split virus vaccine and surface antigen vaccine. These vaccines have many side-effects. Because asthma exacerbations can be triggered by upper-respiratory-tract infections, a large number of asthmatics are vaccinated against influenza each year, but a viral aetiology has not been confirmed in more than 20% of such exacerbations in adults. Influenza vaccination is known to increase bronchial reactivity and cause exacerbations of asthma. 2,3 Some of our patients had exacerbations of asthma after such vaccination and three were admitted, one of whom needed assisted ventilation in the intensive care unit. These cases have been reported to the Committee on Safety of Medicines. We do not recommend an annual influenza vaccine in stable asthmatics, because of the potential side-effects. Perhaps those patients whose asthma is unstable, and who had frequent exacerbations in the previous year after upper-respiratory-tract infections, should be vaccinated with sub-unit vaccine. These vaccines are prepared by separating surface antigens from the core virus by selective solubilisation,4have fewer side-effects, and are well tolerated by a group of moderately severe asthmatics.5 WAJAHAT U. HASSAN
1. Brewis RAL, Gibson GJ, Geddes DM. Respir Med 1990; 17: 648. 2 Dejongste JC, Degenhart HC, Neijens HJ, et al. Bronchial responsiveness and leucocyte reactivity after influenza vaccine m asthmatic patients. Eur J Respir 1984; 65: 196. 3. Oukette JJ, Reed CE. Increased response of asthmatic subjects to methacholine after influenza vaccine. J Allergy 1965; 36: 558-63. 4. Backmayer H. Selective solubilisation of haemagglutinin and neuroaminidase from influenza viruses. Intervirology 1975; 5: 260-68. 5. Albazzaz MK, Harvey JE, Grilli EA, Caul EO, Roome AP. Subunit influenza vaccination in adults with asthma: effects on clinical state, airway reactivity and antibody response. Br Med J 1987; 294: 1196.
Tegernsee giant p
SIR,-Dr Nerlich (Oct 5, p 886) and Dr Schwindinger (Dec 7, 1454) and their colleagues speculate on the possible coexistence of
juvenile gigantism and polyostotic fibrous dysplasia in the Tegemsee giant, but are unaware that this association has already been reported.1 The first of the two patients described was a boy born in Nottingham in 1930, whom I saw in Manchester Royal Infirmary in 1954, and who was still alive, though severely disabled by bone disease, in the late 1960s. Department
1 Ohmon M, Endo T, Onaya T. Development of chicken antibodies toward the human thyrotropin receptor peptides and their bioactivities. Biochem Biophys Res Commun
1991; 174: 399-403. 2. Kosugi S, Ban T, Akamizu T, Kohn LD. Site-directed mutagenesis of a portion of the extracellular domain of the rat thyrotropin receptor important m autoimmune thyroid disease and nonhomologous with gonadotropm receptors. Relationship of functional and immunogenic domains J Biol Chem 1991; 266: 19413-18.
ALLAN F. HENDERSON NIALL P. KEANEY
Royal Infirmary, Sunderland SR2 7JE, UK
of Medicine,
Rayne Institute, University College and Middlesex School of Medicine, London WC1 E 6JJ, UK 1. Falconer
OLIVER WRONG
MA, Cope CL. Fibrous dysplasia of bone with endocrine disorders pigmentation. Q J Med 1942; 11: 121-54.
cutaneous
and