Hereditary fevers

Hereditary fevers are a group of rare disorders of the inflammatory response. Clinical features include recurrent attacks of fever and organ-localized inflammation. Minimal clinical variations, a unique biochemical-specific abnormality, and the mode of genetic inheritance distinguish the three main diseases: familial Mediterranean fever, hyperimmunoglobulinemia D and periodic fever syndrome, and autosomal dominant recurrent fever. The complete elucidation of pathogenesis of these intriguing disorders will be provided by the genetic studies currently in progress.

Increased circulating cytokine receptors and ex vivo interleukin-1 receptor antagonist and interleukin-1beta production but decreased tumour necrosis factor-alpha production after a 5-km run

BACKGROUND

The purpose of this study was to examine the effect of a 5-km run on blood leucocytes, acute-phase proteins and cytokines. In addition, cytokines were measured in the supernatants from whole-blood cell cultures incubated with lipolysaccharide (LPS).

METHODS

Ten healthy, recreational trained, athletes (three women, seven men) volunteered for this investigation. Samples were drawn just before, immediately after and at 3 h, at 24 h and at 48 h after the race.

RESULTS

Exercise induced a transient leucocytosis (P = 0. 0002) and a mild acute-phase reaction with increase in plasma C-reactive protein (CRP) (P = 0.0115) but not in serum amyloid A (SAA) concentrations. Although plasma interleukin 6 (IL-6) was undetectable and soluble interleukin-1 receptor type II (IL-1sRII) remained unchanged, interleukin-1 receptor antagonist (IL-1ra) concentrations were elevated directly after the race with a further increase at 3 h (P < 0.0001). Soluble tumour necrosis factor (TNF) receptors were increased immediately after the run, but the effect was more marked for sTNFr p55 (two-fold increase; P < 0.0001) than for sTNFr p75 (1.16-fold increase; P = 00007). In cell cultures, the LPS-induced release of the inflammatory cytokines doubled for IL-1beta (P < 0.0001) and for IL-1ra (P < 0.0001). In contrast, TNF-alpha production decreased after the run, and a nadir was reached at 24 h (P < 0.0001).

CONCLUSION

These results suggest that a 5-km run elicits both the production of acute-phase mediators (leucocytosis and elevation of CRP) and anti-inflammatory counter-regulation as judged by the increase in circulating concentrations of IL-1ra, sTNFr p55, and sTNFrp75 and down-regulation of LPS-stimulated TNF-alpha production.

Multiple authorship: the contribution of senior authors

CONTEXT

The number of authors per article has increased markedly in recent years. Little is known about the hierarchical order of authorship and its change over time.

OBJECTIVE

To assess the change in number and profile of authors of original articles published over a 20-year period in BMJ. It was hypothesized that the number of authors increased over this 20-year period and that it was the senior scientists who benefited most.

DESIGN

Comparative descriptive analysis of the number and academic rank of authors who published original articles in BMJ volumes 270 (1975), 280 (1980), 290 (1985), 300 (1990), and 310 (1995).

MAIN OUTCOME MEASURES

The specific academic rank, order, and number of authors for each original article. Eight categories of authorship were distinguished as follows: 1, professor; 2, department chairperson; 3, consultant; 4, senior registrar; 5, lecturer and/or registrar; 6, medical student; 7, house officer; and 8, miscellaneous.

RESULTS

The number of original articles published per year decreased from 262 (1975) to 125 (1995). The mean number (SD) of authors per article increased steadily from 3.21 (SD, 1.89) (1975) to 4.46 (SD, 2.04) (1995). Most authors belonged to category 3, and its proportion varied from 24.7% (1975) to 22.6% (1995), while category 1 grew from 13.2% to 20.3%. Category 5 authorship dropped from 24.3% (1975) to 15.8% (1995). With regard to first authorship, category 1 more than doubled from 8.0% (1975) to 16.8% (1995) compared with category 5 whose proportion decreased from 34.0% to 24.8%. Most last authors were from category 1, 20.4% (1975), growing to 29.0% (1995).

CONCLUSION

Over the last 20 years the number of BMJ authors of original articles increased, mainly because of the rise of authorship among professors and department chairpersons.

Regulation of the production of pro-inflammatory cytokines and antagonists during chemotherapy-induced neutropenia in patients with haematological malignancies

Cytokine profiles were studied during 19 episodes of chemotherapy-induced neutropenia in 17 patients with haematological malignancies. Circulating concentrations of interleukin 1 alpha (IL-1 alpha), tumour necrosis factor alpha (TNF-alpha) and IL-1 receptor antagonist (IL-1ra) were measured before chemotherapy and thereafter three times weekly. During and after chemotherapy no significant changes were found in circulating cytokines. After start of chemotherapy, the ex-vivo LPS-stimulated production of cytokines in whole blood decreased and subsequently disappeared completely in all patients, and recovered after the end of treatment. The decrease of cytokine production could not be attributed to the decreased number of cells only, as the net production per circulating neutrophil or monocyte also decreased significantly, and was restored after completion of chemotherapy. These results show that the production of IL-1 beta, TNF-alpha and IL-1ra in blood disappears during chemotherapy-induced neutropenia, not only due to the decreased number of producing cells, but also as a result of a decreased production per cell, suggesting a mechanism of downregulation.

Familial Mediterranean fever and hyperimmunoglobulinemia D syndrome: two diseases with distinct clinical, serologic, and genetic features

OBJECTIVE

To determine whether the 2 periodic febrile syndromes familial Mediterranean fever (FMF) and hyperimmunoglobulinemia D syndrome (HIDS) are distinct diseases.

METHODS

Clinical manifestations of the diseases were analyzed by physicians experienced with FMF and HIDS. Serum immunoglobulin (Ig) levels were studied in 70 patients with FMF using nephelometry or ELISA and compared with Ig levels in 50 patients with HIDS. Genetic linkage of HIDS with the chromosome 16 polymorphic locus RT70, currently used for refined localization of the FMF susceptibility gene (MEFV), was studied in 9 HIDS families (18 patients) using polymerase chain reaction amplification and gel electrophoresis.

RESULTS

The main clinical features distinguishing FMF from HIDS were lymphadenectomy, skin eruption, and symmetrical oligoarthritis in HIDS, and monoarthritis, peritonitis, and pleuritis in FMF. Increased IgG levels were found in 12 patients with FMF (17%), IgA in 16 (23%), IgM in 9 (13%), and IgD in 9 (13%), significantly lower than the prevalence reported for HIDS. We found no evidence for genetic linkage between HIDS and the chromosome 16 marker RT70.

CONCLUSION

HIDS and FMF are different entities, clinically, immunologically, and genetically.

Circulating and ex vivo production of pyrogenic cytokines and interleukin-1 receptor antagonist in 123 patients with fever of unknown origin. The Netherlands Fever of Unknown Origin Study Group

Circulating and ex vivo production of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-6, and IL-1 receptor antagonist (ra) and the diagnostic utility of these cytokines were studied in 123 patients with fever of unknown origin (FUO). Diagnoses were infections, 28; neoplasms, 14; noninfectious inflammatory diseases (NIID), 32; miscellaneous diseases, 10; and none made, 39. IL-1beta, IL-6, and IL-1ra concentrations were higher in patients with infections, neoplasms, and NIID than in healthy controls. Patients with infections had higher concentrations of TNF-alpha than controls. The ex vivo production of IL-1beta and IL-1ra in all patients with FUO did not differ from that in controls; however, production of TNF-alpha was lower in patients with neoplasms and NIID, and IL-6 production was lower in patients with neoplasms. Thirty-five patients with fever did not have elevated cytokines. Although some significant differences were found among the diagnostic subgroups, there was wide variation. Thus, measurement of these cytokines does not aid in the diagnosis of FUO.

Hyper-IgD syndrome and pregnancy

In this report two cases of the coincidence of hyperimmunoglobulinemia D syndrome (HIDS) and pregnancy are described. HIDS is not associated with complications in pregnancy or disturbance in fetal outcome; the frequency of attacks diminishes during pregnancy; HIDS probably inherits via an autosomal recessive trait and is not transmitted to children of patients.

A semi-quantitative reverse transcriptase polymerase chain reaction method for measurement of MRNA for TNF-alpha and IL-1 beta in whole blood cultures: its application in typhoid fever and exentric exercise

Whole blood cultures are used to study cytokine stimulation and release ex vivo. In the present study this method was compared with a more direct approach and a quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to assess mRNA expression for IL-1 beta and tumour necrosis factor alpha (TNF-alpha) and mRNA in whole blood. Stimulation of whole blood from normal donors with lipopolysaccharide (LPS) at various time intervals showed a parallel rise of immunogenic IL-1 beta and TNF-alpha as well as a rise of mRNA expression for IL-1 beta and TNF-alpha with peak levels for IL-1 beta after 4-6 h stimulation and for mRNA TNF-alpha expression after 2 h stimulation. These methods were used to explore cytokine production during the course of typhoid fever and after a 5 km run. In both conditions circulating cytokine concentrations were not influenced, but the TNF-alpha and IL-1 beta mRNA gene expression in circulating whole blood cells was increased in patients with typhoid fever. The LPS-stimulated production of TNF-alpha and IL-1 beta was decreased in both but there was no change for the mRNA content in whole blood for these cytokines. These findings demonstrate that RT-PCR is an attractive method to study the gene expression of cytokines in whole blood, an increased TNF-alpha and IL-1 beta gene expression is present in typhoid fever, and that the LPS stimulated downregulation of cytokines in exercise and typhoid fever may be mediated by post-transcriptional processes.

Unstimulated peripheral blood mononuclear cells from patients with the hyper-IgD syndrome produce cytokines capable of potent induction of C-reactive protein and serum amyloid A in Hep3B cells

The hyper-IgD and periodic fever syndrome (HIDS) and familial Mediterranean fever (FMF) are both characterized by attacks of periodic fever accompanied by acute phase responses that are substantially higher in HIDS than in FMF. To determine whether this difference could be due to differences in production of acute phase protein-inducing mediators, we studied PBMC from HIDS and FMF patients in the inactive phase of disease. Unstimulated PBMC from patients with inactive HIDS released significantly more IL-1 beta, IL-6, and TNF-alpha than did PBMC from patients with FMF, but unstimulated PBMC from the latter group released significantly more IL-1 beta and IL-6 compared with controls. Conditioned medium (CM) derived from PBMC of patients with inactive HIDS induced significantly greater CRP production and significantly higher mRNAs for CRP and SAA in Hep3B cells than did CM derived from the PBMC of patients with inactive FMF. Stimulation of PBMC with LPS led to further increases in cytokine production and in acute phase protein-inducing ability in both patient groups and in controls. These findings suggest that the greater acute phase response seen in HIDS compared with FMF reflects greater production of acute phase protein-inducing cytokines in the former patients and indicates that PBMC from inactive HIDS patients are already activated in vivo. Finally, the finding of both quantitative and qualitative differences in cytokine production by unstimulated PBMC from HIDS and FMF patients supports the likelihood of different pathogeneses of these diseases.

Immunoglobulin D enhances the release of tumor necrosis factor-alpha, and interleukin-1 beta as well as interleukin-1 receptor antagonist from human mononuclear cells

Immunoglobulin D (IgD) is normally present in only low concentrations in serum. In the hyper-IgD and periodic fever syndrome (HIDS), however, serum levels exceed 140 mg/l. This syndrome is further characterized by recurrent inflammatory febrile attacks together with an acute phase response and appearance of cytokines in the circulation. The role of IgD in the pathogenesis of HIDS and its relation to the increased cytokine concentrations is unclear. Therefore, we tested whether IgD, IgG and alpha 1-acid glycoprotein (AGP) isolated from human serum influence the synthesis of interleukin-1 beta (IL-1 beta), tumour necrosis factor-alpha (TNF-alpha), and IL-1ra, as measured by specific radioimmunoassays, in human peripheral blood mononuclear cells (PBMC). Incubation of PBMC with IgD and AGP for 24 hr led to increased release of IL-1 beta, TNF-alpha, and IL-lra. The magnitude of stimulation of IgD exceeded that of AGP; the effect by IgD was dose-dependent and showed a 30-fold (TNF-alpha) to almost 150-fold (IL-1 beta) increase at the highest concentration (50 mg/l), while AGP (750 micrograms/ml) only increased the cytokine secretion fourfold (TNF-alpha) to almost 30-fold (IL-1 beta). The effect of IgD on IL-1ra was less dramatic but a fivefold increase was observed at 50 mg/l compared with a 2.5-fold increase with AGP. IgD potentiated the effect of lipopolysaccharide (LPS) on secretion of both IL-1 beta and TNF-alpha, although the effect was most apparent for TNF-alpha. Apart from inducing IL-1ra synthesis, IgG did not influence cytokine release in human PBMC. These data indicate that IgD is a potent inducer of TNF-alpha, IL-1 beta and IL-1ra and thus may contribute to the pathogenesis of HIDS.

Unstimulated peripheral blood mononuclear cells from patients with the hyper-IgD syndrome produce cytokines capable of potent induction of C-reactive protein and serum amyloid A in Hep3B cells

The hyper-IgD and periodic fever syndrome (HIDS) and familial Mediterranean fever (FMF) are both characterized by attacks of periodic fever accompanied by acute phase responses that are substantially higher in HIDS than in FMF. To determine whether this difference could be due to differences in production of acute phase protein-inducing mediators, we studied PBMC from HIDS and FMF patients in the inactive phase of disease. Unstimulated PBMC from patients with inactive HIDS released significantly more IL-1 beta, IL-6, and TNF-alpha than did PBMC from patients with FMF, but unstimulated PBMC from the latter group released significantly more IL-1 beta and IL-6 compared with controls. Conditioned medium (CM) derived from PBMC of patients with inactive HIDS induced significantly greater CRP production and significantly higher mRNAs for CRP and SAA in Hep3B cells than did CM derived from the PBMC of patients with inactive FMF. Stimulation of PBMC with LPS led to further increases in cytokine production and in acute phase protein-inducing ability in both patient groups and in controls. These findings suggest that the greater acute phase response seen in HIDS compared with FMF reflects greater production of acute phase protein-inducing cytokines in the former patients and indicates that PBMC from inactive HIDS patients are already activated in vivo. Finally, the finding of both quantitative and qualitative differences in cytokine production by unstimulated PBMC from HIDS and FMF patients supports the likelihood of different pathogeneses of these diseases.

Cutaneous pathology in primary erythermalgia

Primary or idiopathic erythermalgia is characterized by recurrent, red, warm, and painful lower extremities. It arises at young age and persists throughout life because no treatment is available. We report the cutaneous pathology of affected skin lesions of three patients with primary erythermalgia. Biopsy specimens showed a mild perivascular mononuclear infiltrate, thickened blood vessel basement membranes, abundant perivascular edema, and moderate endothelial swelling. The thickened basal membrane of the blood vessels showed a laminar structure, and abundant perivascular edema and moderate endothelial cell swelling were evident. These histopathologic findings in primary erythermalgia appear to be nonspecific but allow diagnostic differentiation from erythromelalgia in which fibromuscular intimal proliferation and occlusive thrombi in the endarteriolar capillaries are apparent and from erythermalgia secondary to vasculitis. Histopathologic examination of affected skin lesions in patients with red, congested, warm, and painful burning extremities is a valuable tool in the diagnostic process.

Acute secondary erythermalgia and hypertension in children. Erythermalgia Multidisciplinary Study Group

We studied the clinical symptoms in nine children (seven females and two males; mean age 11.6 years) with severe but transient acute secondary erythermalgia. The classical symptoms at presentation were episodic attacks of painful burning hands and feet which felt warm with congested appearance of the feet. Each attack lasted for a mean period of 25 days (range from 6 to 56 days). The blood pressure was elevated in seven patients. Intravenous sodium nitroprusside was effective in ameliorating the symptoms with drop in blood pressure to normal in five patients; pizotifene, labetolol, prostaglandin E1 and hypnotherapy were effective in each of four separate cases. The episodes of acute secondary erythermalgia were transient in all and did not recur after a mean follow up period of 1.6 years. These cases suggest that acute secondary erythermalgia, however transient, is not rare and can be associated with mild to moderate hypertension which may respond to sodium nitroprusside. A greater awareness of this condition is necessary to make an accurate and timely diagnosis and institute appropriate therapy in order to prevent undue complications.

Endurance run increases circulating IL-6 and IL-1ra but downregulates ex vivo TNF-alpha and IL-1 beta production

We investigated whether a 6-h endurance run changes cytokine plasma concentrations and lipopolysaccharides (LPS) stimulated ex vivo production of cytokines in a whole blood culture of 19 well-trained athletes. The average distance covered was 65.1 +/- 8.64 (SD) km. At the end of the exercise, the mean plasma concentration of interleukin-1-receptor agonist (IL-1ra), which was 188 pg/ml 24 h before finish, increased to 886 pg/ml (P < 0.0005). The mean plasma interleukin-6 concentration increased from 18.5 +/- 4.2 to 71.5 +/- 33.3 pg/ml (P < 0.0001). The increase of neutrophils correlated with the increase of IL-1ra concentrations (r = 0.58, P < 0.005). We could not detect an effect of exercise on plasma concentrations of interleukin-1 beta (IL-1 beta) or tumor necrosis factor-alpha (TNF-alpha). The ex vivo LPS-stimulated production of IL-1 beta in athletes 24 h before the run was significantly higher than in sedentary controls. Exercise induced a decrease of LPS-stimulated production of IL-1 beta and TNF-alpha, whereas production of IL-1ra was unchanged. These results show that prolonged exercise elicits a selective downregulation of the proinflammatory cytokine production and upregulation of the cytokines IL-1ra and interleukin-6.

[Hyperimmunoglobulin D syndrome]

The hyper-IgD syndrome is a rare entity characterized by early onset of attacks of periodic fever. All patients have an elevated serum IgD (> 100 U/ml). Symptoms during attacks include joint involvements (arthralgias/arthritis), abdominal complaints (vomiting, pain, diarrhoea), skin lesions, swollen lymph nodes, and headache. In 1992 an International hyper-IgD study group was established, and to date the diagnosis has been made in 60, mainly European patients; 14 come from France. The disorder occurs in families and is transmitted by autosomal recessive inheritance. Linkage studies indicate that the gene encoding for familial Mediterranean fever is different from the gene for the hyper-IgD syndrome. In children the hyper-IgD syndrome should be distinguished from two other periodic febrile disorders. CINCA (chronic inflammatory, neurological, cutaneous and articular syndrome) and FAPA (periodic fever, adenopathies, pharyngitis, and aphtous stomatitis) share some symptoms with the hyper-IgD syndrome but in these syndromes serum IgD is normal. The pathogenesis remains to be elucidated but during attacks all patients have an acute-phase response with elevated C-reactive protein concentrations. During the febrile episodes, the inflammatory cytokines such as IL-6 TNF alpha, IFN gamma are increased together with natural occurring inhibitors such as IL-1ra and sTNFr. There is no therapy for the syndrome and patients will experience attacks during their entire life although frequency and severity tend to diminish with age.