Serious bacterial infections in patients with rheumatoid arthritis under anti-TNF-alpha therapy

OBJECTIVE

With rising numbers of anti-tumour necrosis factor alpha (TNF-alpha) treatments for rheumatoid arthritis (RA), Crohn's disease and other conditions, physicians unaware of potential pitfalls are increasingly likely to encounter associated severe infections. Our purpose was to assess the incidence and nature of severe infections in our RA patients under anti-TNF-alpha therapy.

METHODS

We reviewed patient charts and records of the Infectious Disease Unit for serious infections in patients with RA in the 2 yr preceding anti-TNF-alpha therapy and during therapy.

RESULTS

Serious infections affected 18.3% of patients treated with infliximab or etanercept. The incidence was 0.181 per anti-TNF-alpha treatment year vs 0.008 in the 2 yr preceding anti-TNF-alpha therapy. In several cases, only a few signs or symptoms indicated the severity of developing infections, including sepsis.

CONCLUSIONS

A high level of suspicion of infection is necessary in patients under anti-TNF-alpha therapy. We suggest additional strategies for the prevention, rapid identification and pre-emptive therapy of such infections.

Clinical evaluation of the WOMAC 3.0 OA Index in numeric rating scale format using a computerized touch screen version

BACKGROUND

The Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index is a previously described self-administered questionnaire covering three domains: pain, stiffness and function. It has been validated in patients with osteoarthritis (OA) of the hip or knee in a paper-based format.

AIM

To validate the WOMAC 3.0 using a numerical rating scale in a computerized touch screen format allowing immediate evaluation of the questionnaire. In the computed version cartoons, written and audio instruments were included in order facilitate application.

METHODS

Fifty patients, demographically balanced, with radiographically proven primary hip or knee OA completed the classical paper and the new computerized WOMAC version. Subjects were randomized either to paper format or computerized format first to balance possible order effects.

RESULTS

The intra-class correlation coefficients for pain, stiffness and function values were 0.915, 0.745 and 0.940, respectively. The Spearman correlation coefficients for pain, stiffness and function were 0.88, 0.77 and 0.87, respectively.

CONCLUSION

These data indicate that the computerized WOMAC OA index 3.0 is comparable to the paper WOMAC in all three dimensions. The computerized version would allow physicians to get an immediate result and if present a direct comparison with a previous exam.

Induction of an acute attack of calcium pyrophosphate dihydrate arthritis by intra-articular injection of hylan G-F 20 (Synvisc)

Little is known about the induction of acute calcium pyrophosphate dihydrate arthritis after the intra-articular injection of hylan G-F 20 (Synvisc). Two reports have documented this adverse effect after the intra-articular injection of hyaluronan. Our patient, a 60-year-old man with osteoarthritis in both knees, presented with a history of an arthroscopy with meniscus shaving 7 years previously. He was given an injection of hylan G-F 20 in the right knee joint. Two days after the second injection, pain and swelling of the knee occurred. There was a severe loss of physical function. Systemic inflammatory reactions such as fever were not observed. A microscopic investigation of the synovial fluid showed evidence of calcium pyrophosphate dihydrate crystals. Bacterial contamination was not detected. There was no indication for calcium pyrophosphate dihydrate in the history of the patient. Some days after receiving nonsteroidal anti-inflammatory drugs and an intra-articular injection of steroids, the symptoms disappeared.

Plasticity of neuropeptide Y in the rat superior cervical ganglion in response to nerve lesion

Axotomy of the rat superior cervical ganglion results in a two-fold increase of neuropeptide tyrosine as determined by radioimmunoassay. On the other hand, treatment of sympathetic neuron cultures with leukemia inhibitory factor, a cytokine that is known to be involved in the up-regulation of galanin after axotomy in vivo, decreases neuropeptide tyrosine messenger RNA. These, apparently contradictory findings, prompted us to investigate the regulation of neuropeptide tyrosine in the axotomized superior cervical ganglion in vivo. For comparison, the regulation of galanin was examined under the same conditions. Compared to control ganglia, the number of neuropeptide tyrosine-positive cell bodies decreased while the density of immunoreactive neuronal processes increased one week after transection of the major postganglionic nerves. The nerve fibres were identified as axons by the absence of MAP2, a somatodendritic marker protein. They extended into both carotid nerves and ramified at the lesion site. In situ hybridization revealed that, although the number of neuropeptide tyrosine messenger RNA-positive neurons was not different from controls, the average grain density/neuron decreased by 40%. When axotomized ganglia were decentralized simultaneously, a three-fold elevation of neuropeptide tyrosine immunoreactivity was detectable by radioimmunoassay and an additional increase in numerical density of neuropeptide tyrosine-immunoreactive nerve fibres was observed. Levels of neuropeptide tyrosine messenger RNA were significantly reduced within postganglionic neurons. This synergistic effect of combined axotomy and decentralization on peptide content was also detected for the neuropeptide galanin that, in contrast to neuropeptide tyrosine, is induced by axotomy or decentralization on protein and messenger RNA level. Therefore, while neuropeptide tyrosine messenger RNA is reduced in axotomized ganglia (most likely in response to leukemia inhibitory factor), the peptide accumulates in axonal processes resulting in increased peptide levels as determined by radioimmunoassay.

Secretoneurin: a market in rat hippocampal pathways

Secretoneurin is a 33-amino acid peptide, generated in brain by proteolytic processing of secretogranin II. The distribution of secretoneurin-like immunoreactivity and secretogranin II mRNA was investigated in the hippocampus of the rat. Secretogranin II mRNA was found in high concentrations throughout the granule cell and pyramidal cell layers and in many local neurons, notably in the hilus of the dentate gyrus. The general distributional pattern of secretoneurin-like immunoreactivity was characterized by a prominent staining in the area of the terminal field of mossy fibers with an obvious staining in the infrapyramidal area of CA3 and a strongly immunopositive band in the inner third of the molecular layer of the dentate gyrus. Lesions of the granule cells by local injection of colchicine significantly reduced secretoneurin-like immunoreactivity in the terminal field of mossy fibers, but not in the inner molecular layer of the dentate gyrus. On the other hand, destruction of interneurons of the dentate gyrus (mossy cells and certain gamma-aminobutyricacid-ergic interneurons) by kainic acid-induced seizures was associated with a reduction of secretoneurin-like immunoreactivity in the inner molecular layer of the dentate gyrus. However, 30 days after kainic acid-induced seizures, a strongly secretoneurin-immunoreactive band reappeared in this area, which at this late time point is due to sprouting of mossy fibers collaterals. Our experiments suggest a widespread distribution of secretoneurin-like immunoreactivity in neurons of the hippocampal formation with a preferential localization in excitatory pathways including associational/commissural fibers originating from secretoneurin-containing mossy cells.

Rat brain: distribution of immunoreactivity of PE-11, a peptide derived from chromogranin B

An antiserum was raised against the peptide PE-11 whose sequence is present in the chromogranin B molecule. The antiserum reacts only with the free C-terminal end of this peptide. PE-11 immunoreactivity in brain was characterized by molecular size exclusion high performance liquid chromatography. Only the free peptide and a N-terminally elongated peptide were detected, indicating that proteolytic processing of chromagranin B in brain is quite extensive. In immunohistochemistry PE-11 immunoreactivity was found in varicosities, fibres and perikarya throughout the brain. Strong staining was detected in the shell sector of the nucleus accumbens, in the lateral septum, in subregions of the extended amygdala, in some areas of the hippocampus and of the hypothalamus, in the locus coeruleus, in the Purkinje cells of the cerebellum and in the dorsal horn of the spinal cord. Our results, which demonstrate significant processing of chromogranin B in brain and its widespread distribution, can be taken as an indication that chromogranin B represents a precursor of peptides with functional relevance for this organ.

Localization and axotomy-induced regulation of the peptide secretoneurin in the rat superior cervical ganglion

This study demonstrates the localization and regulation of a novel neuropeptide of 33 amino acids, secretoneurin (SN), in the rat superior cervical ganglion. Gel filtration chromatography of ganglion proteins followed by a specific radioimmunoassay revealed that SN is the predominant cleavage product of secretogranin II, a member of the chromogranin/secretogranin protein family, in adult ganglia. SN was detected within the majority of nerve endings surrounding postganglionic neurons that were identified by the presence of synaptophysin and, in part, colocalized leu-encephalin. Applying immuno-electronmicroscopy, SN was localized to large dense core vesicles of neuronal and small intensely fluorescent (SIF) cells. In situ hybridization revealed the presence of secretogranin II mRNA in postganglionic neurons and, to a lesser extent, in SIF cells. One week after transection of the postganglionic branches SN levels were not significantly altered; however, a decrease of secretogranin II mRNA was observed in postganglionic neurons but not in SIF cells. After decentralization of the ganglion, SN-immunoreactive nerve terminals disappeared and intraganglionic SN levels were reduced by 70%, indicating the preganglionic origin of SN-positive nerve fibres and varicosities. Secretogranin II mRNA was slightly reduced under this condition. Combined axotomy and decentralization further diminished intraganglionic secretogranin II mRNA, although peptide levels increased significantly above control values under these conditions. Double-labelling immunofluorescence with antibodies against the somatodendritic marker microtubule-associated protein 2 (MAP2) revealed that the increase in SN immunoreactivity was due to an accumulation of SN in axonal processes of postganglionic neurons. SN immunoreactivity was also detected in dissociated neonatal superior cervical ganglion cultures and increased significantly upon treatment with nerve growth factor, the survival and differentiation factor of sympathetic neurons during perinatal development. Co-culture with non-neuronal cells or addition of leukaemia inhibitory factor, a cytokine known to stimulate synthesis of various peptides after nerve transection, did not influence SN immunoreactivity. Therefore, since no fixed relationship between SN and any of the known neuropeptides or neurotransmitters expressed in sympathetic neurons was observed, the expression of this novel peptide appears to be independently regulated.

Effects of haloperidol, clozapine and citalopram on messenger RNA levels of chromogranins A and B and secretogranin II in various regions of rat brain

We have measured the messenger RNA levels of chromogranins A and B and secretogranin II in various brain regions of rats subchronically treated with various antipsychotic drugs. Since, as shown previously, the messenger RNA levels of these peptides are increased when neurons are stimulated, we hoped to identify by this approach those nuclei which are subchronically influenced by these drugs. The drugs chosen were the neuroleptic halperidol, a blocker of dopamine receptors, the atypical antipsychotic clozapine, which in addition to blocking dopamine receptors also blocks those for serotonin, and citalopram, a specific serotonin reuptake inhibitor. In agreement with previous data on neuropeptide messenger RNAs, we found in the dorsolateral striatum an increase of the secretogranin II messenger RNA levels after haloperidol and a much smaller one after clozapine. In the nucleus accumbens and in the bed nucleus of the stria terminalis, both compounds had a comparable positive effect. These differential effects can be attributed to a different action of these drugs on dopamine receptor subtypes. In the zona incerta, clozapine decreased the secretogranin II and chromogranin A message, whereas in the dorsal raphe it led to an increase. On the other hand, citalopram induced exactly the opposite effects in these two brain regions. This phenomenon can be explained by the differential interaction of these drugs with serotonergic mechanisms. Additional, relatively small changes of the mRNAs were seen in several other brain regions. These results establish that changes in the mRNA levels of the chromogranins are good indicators for the effect of drugs on certain brain nuclei. The concomitant action of haloperidol and clozapine on the limbic regions, i.e. the nucleus accumbens and the bed nucleus of the stria terminalis, points to these brain regions for the antipsychotic action of these two neuroleptics.

Biosynthesis of large dense-core vesicles in PC12 cells: effects of depolarization and second messengers on the mRNA levels of their constituents

mRNA levels of various constituents of large dense-core vesicles were determined in PC12 cells during depolarization and/or in the presence of BayK 8644, forskolin or phorbolester. For the soluble (secretory) proteins of the vesicles the mRNAs of chromogranin A and B, secretogranin II, neuropeptide Y and VGF were analyzed. Depolarization in the presence of BayK induced a strong up-regulation of the messages for chromogranin B, neuropeptide Y and VGF. Addition of forskolin enhanced this response for neuropeptide Y and VGF, phorbolester did the same only for VGF. Partly membrane-bound and membrane-spanning components analyzed were carboxypeptidase H, dopamine beta-hydroxylase and glycoprotein III (clusterin), peptidylglycine alpha-amidating mono-oxygenase and cytochrome b-561, respectively. Changes of mRNAs for these components were in general smaller and delayed. Six days of depolarization caused an up-regulation of glycoprotein III, peptidylglycine alpha-amidating mono-oxygenase and carboxypeptidase H mRNA levels which were not further increased by cyclic AMP and phorbolester. The dopamine beta-hydroxylase message increased after 6 days of depolarization, however, addition of phorbolester reduced this effect. For cytochrome b-561 there was no change after any of the conditions employed. These in vitro results are compared with those obtained for the biosynthesis regulation of large dense-core vesicles under in vivo conditions. It is suggested that in vivo acetylcholine and vasoactive intestinal polypeptide released from splanchnic nerve induce a differential change in the biosynthesis of large dense-core vesicles by acting via calcium and protein kinase A and C.

Evidence for a high density of secretoneurin-like immunoreactivity in the extended amygdala of the rat

Secretoneurin is a novel 33-amino-acid neuropeptide produced by endoproteolytic processing from secretogranin II, which is a member of the chromogranin/secretogranin family. In this immunocytochemical study, we compared the distribution pattern of secretoneurin immunoreactivity with that of tyrosine hydroxylase, calbindin, substance P, and Leu-enkephalin in adjacent sections of rat forebrain. Secretoneurin appeared mainly in varicosities and fibers. Only a few cell bodies were stained. In the nucleus accumbens, a partial overlap of secretoneurin-immunoreactive patches with enkephalin-immunopositive areas was found. Secretoneurin displayed low to moderate levels of immunoreaction in calbindin-rich as well as in calbindin-immunonegative areas of the caudate-putamen. In the globus pallidus, entopeduncular nucleus, and substantia nigra, secretoneurin immunoreactivity was oriented ventromedially preferentially in woolly fibers. The dense immunostaining in the medial nucleus accumbens was directly continuous with dense secretoneurin immunoreactivity in the bed nucleus of the stria terminalis. Two strongly secretoneurin-immunopositive bands, one in the sublenticular portion and a smaller one along the posterior limb of the anterior commissure, interconnected the highly secretoneurin-immunopositive centromedial amygdala with the bed nucleus of the stria terminalis. Thus, the distribution pattern of secretoneurin immunoreactivity provides a marker of the extended amygdala that forms a continuum between the centromedial amygdala and the bed nucleus of the stria terminalis.