Isatuximab in combination with cemiplimab in patients with relapsed/refractory multiple myeloma: A phase 1/2 study

BACKGROUND

Given the incurable nature of multiple myeloma (MM), efforts are made to improve the efficacy of anti-CD38 monoclonal antibodies via combinations with other potentially synergistic therapies. This Phase 1/2 trial (NCT03194867) was designed to determine whether cemiplimab (anti-PD-1) enhances the anti-myeloma activity of isatuximab (anti-CD38) in patients with relapsed and refractory multiple myeloma (RRMM), to confirm the feasibility of the combination, determine its efficacy, and further evaluate its safety.

METHODS

Patients received isatuximab 10 mg/kg once weekly for 4 weeks followed by every 2 weeks (Isa), or isatuximab 10 mg/kg plus cemiplimab 250 mg every 2 (Isa + CemiQ2W) or every 4 weeks (Isa + CemiQ4W).

RESULTS

Overall, 106 patients with RRMM treated with a median of 4 prior lines were included; 25.5% had high-risk cytogenetics, 63.2% were refractory to proteasome inhibitors and immunomodulatory agents, 26.4% were previously exposed to daratumumab, and 84.0% were refractory to their last treatment line. There were no major changes in the safety or pharmacokinetic profile of isatuximab with the addition of cemiplimab. As assessed by investigators, four patients (11.8%) in the Isa arm, nine patients (25.0%) in the Isa + CemiQ2W arm, and eight patients (22.2%) in the Isa + CemiQ4W arm were responders. Though response rates were numerically higher in cemiplimab-containing arms, differences were not statistically significant and did not translate to improved progression-free or overall survival after a median follow-up of 9.99 months.

CONCLUSION

Our results suggest a marginal benefit by adding cemiplimab to isatuximab, despite demonstration of target engagement, without additional observed safety issues.

Clinical/serological outcome in humans bitten by Babesia species positive Ixodes ricinus ticks in Sweden and on the Åland Islands

The risk of contracting babesiosis after a tick bite in Sweden and on the Åland Islands, Finland, is unknown. We investigated clinical and serological outcomes in people bitten by Ixodes ricinus ticks positive for Babesia species. Ticks, blood and questionnaires were obtained from study participants in Sweden and on the Åland Islands. Sixty-five of 2098 (3.1 %) ticks were positive by real-time PCR. Three Babesia species were detected, Babesia microti (n = 33), B. venatorum (n = 27) and B. capreoli (n = 5), the latter species not known to cause human infection. Half (46 %) of the Babesia PCR-positive ticks also contained Borrelia spp. Fifty-three participants bitten by a Babesia PCR-positive tick and a control group bitten by a Babesia PCR-negative tick were tested for B. microti IgG antibodies by IFA. The overall seroprevalence was 4.4 %, but there was no significant difference between the groups. None of the participants seroconverted and no participant with a Babesia PCR-positive tick sought medical care or reported symptoms suggestive of babesiosis. Given the prevalence of Babesia in I. ricinus ticks in southern Sweden and on the Åland Islands, babesiosis should be considered a possible diagnosis in symptomatic residents who seek medical care following tick exposure.

Monoclonal Antibodies in Multiple Myeloma: A New Wave of the Future

In 2015, 2 monoclonal antibodies were approved for the treatment of relapsed or refractory multiple myeloma (RRMM), elotuzumab and daratumumab. Elotuzumab is a monoclonal IgG-κ antibody directed against SLAMF7 (signaling lymphocytic activation molecule F7), a cell surface receptor involved in natural killer cell activation. Daratumumab is a monoclonal IgG-κ antibody that binds to CD38, a transmembrane protein found on the surface of myeloma cells and responsible for cellular adhesion and ectoenzymatic activity. Both elotuzumab and daratumumab act through recruitment of the immune system to enhance cellular cytotoxicity directed against myeloma cells. Elotuzumab requires lenalidomide and dexamethasone combined to enhance progression-free survival in patients with RRMM, and daratumumab has both single-agent and combination activity with either lenalidomide or the proteasome inhibitor bortezomib in RRMM. The adverse effect profile of both agents mainly consists of allergic-type infusion reactions. Other considerations for monoclonal antibody use in the treatment of MM include the potential for interference in serum protein electrophoresis testing and cross-reactivity of daratumumab with CD38 present on red blood cells. In the present report, we discussed the clinical development of daratumumab and elotuzumab and newer immunologic approaches to the treatment of MM.

A Phase I Trial of High-Dose Lenalidomide and Melphalan as Conditioning for Autologous Stem Cell Transplantation in Relapsed or Refractory Multiple Myeloma

Autologous stem cell transplantation (ASCT) conditioned with high-dose chemotherapy has long been established as the standard of care for eligible patients with newly diagnosed multiple myeloma. Despite recent therapeutic advances, high-dose melphalan (HDM) remains the chemotherapy regimen of choice in this setting. Lenalidomide (LEN) in combination with low-dose dexamethasone is recognized as a standard of care for patients with relapsed or refractory multiple myeloma (RRMM), and there is growing support for the administration of LEN as maintenance therapy post-ASCT. In view of the above, the present phase I clinical trial was designed to evaluate the safety and tolerability of high-dose LEN (HDLEN) in patients with RRMM, and to determine the maximum tolerated dose of HDLEN when added to HDM before ASCT. Despite administering HDLEN at doses of up to 350 mg/day, the maximum tolerated dose could not be determined, owing to an insufficient number of dose-limiting toxicities in the 21 patients enrolled in the trial. Conditioning with HDLEN plus HDM was associated with a favorable tolerability profile. Adverse events following ASCT were as expected with HDM. Median progression-free and overall survival were 10 months and 22 months, respectively, in this population of heavily pretreated patients. Our findings suggest that HDLEN in combination with HDM may offer significant potential as a conditioning regimen before ASCT in patients with RRMM. These preliminary findings are now being evaluated further in an ongoing phase II clinical trial.

Autism in 3-6-Year-Old Children in a Suburb of Goteborg, Sweden

1941 ofthe 3-6-year-old children living in a community outside Gbteborg on the Swedish west coast were screened with a view to identifying all individuals with severe degrees of autistic behaviour. All children in the population were known to well baby clinic staff, and any child suspected of suffering from autism was referred to a specialized clinical research team. The nurses and doctors working in the well baby clinics were well informed about autism. Clinical and ADI-R diagnoses of autism were established after thorough clinical assessments of each suspected case. All children were seen at least twice, and all were over the age of 3 years at the time of diagnosis. The general population prevalence for autism was 3 I in I o,ooo children (9; percent confidence interval 7/ g;). Classic Kanner autism was found in I o in Io,ooo children (9; percent confidence interval-4/24). These rates appear to reflect higher rates than previously reported. Some reasons for the possibly higher prevalence are discussed.

Role of novel anticoagulants for patients with mechanical heart valves

The introduction of the target-specific oral anticoagulants (TSOACs) has led to a major shift in the management of patients at risk for thrombosis. The landscape continues to evolve as the evidence regarding their efficacy and safety in various clinical situations emerges. Antithrombotic therapy for thromboprophylaxis in patients with mechanical heart valves is challenging. To date, the RE-ALIGN trial comparing dabigatran etexilate to warfarin is the only randomized controlled study in this patient population. The higher risk of thromboembolic and bleeding events in the group of patients who received dabigatran compared with warfarin reinforced current guidelines recommending against the use of TSOACs in patients with mechanical heart valves. However, additional studies are needed to find suitable alternatives to vitamin K antagonists in this unique patient population.

Hematopoietic transplant-associated thrombotic microangiopathy: case report and review of diagnosis and treatments

Transplant-associated thrombotic microangiopathy (TA-TMA) refers to inflammatory and thrombotic diseases of the microvasculature characterized by hemolytic anemia, thrombocytopenia, and evidence of organ damage, particularly acute renal failure. This syndrome occurs in 10% to 20% of patients with allogeneic hematopoietic stem cell transplants (HSCTs). It is much less frequent in the autologous setting. TA-TMAs present diagnostic challenges because they may not clearly fall into one of the categories of the 2 major TMAs: atypical hemolytic uremic syndrome (aHUS) and thrombotic thrombocytopenic purpura (TTP). In addition, complications of the transplant itself, including infection, graft-versus-host disease, and disseminated intravascular coagulation, as well as the side effects of immunosuppressive drugs, can mimic a TMA. Because the pathophysiology of TA-TMA is poorly understood, current treatment options are suboptimal, and the condition carries a very high mortality rate. In 3 recent case summaries, the median acute response rate to plasma exchange was as high as 55%, but this therapy failed to alter underlying disease pathology and had little impact on overall mortality, which was approximately 80%. Indeed, the vast majority of TA-TMA patients lack suppression of ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity to less than 5% to 10% of normal and do not have a complete response to plasma exchange, characteristics indicating that a TTP-like disorder is not involved. Recent advances in the treatment of aHUS may offer a therapeutic option in the aHUS-like TMAs associated with HSCTs. These issues are discussed in the context of a patient recently evaluated and treated at our institution; the case serves to illustrate the difficulties associated with the diagnosis and treatment of TA-TMA.

Seroreactivity for spotted fever rickettsiae and co-infections with other tick-borne agents among habitants in central and southern Sweden

Patients seeking medical care with erythema migrans or flu-like symptoms after suspected or observed tick bite in the southeast of Sweden and previously investigated for Borrelia spp. and/or Anaplasma sp. were retrospectively examined for serological evidence of rickettsial infection (Study 1). Twenty of 206 patients had IgG and/or IgM antibodies to Rickettsia spp. equal to or higher than the cut-off titre of 1:64. Seven of these 20 patients showed seroconversion indicative of recent or current infection and 13 patients had titres compatible with past infection, of which five patients were judged as probable infection. Of 19 patients with medical records, 11 were positive for Borrelia spp. as well, and for Anaplasma sp., one was judged as positive. Five of the 19 patients had antibodies against all three pathogens. Erythema migrans or rash was observed at all combinations of seroreactivity, with symptoms including fever, muscle pain, headache and respiratory problems. The results were compared by screening an additional 159 patients (Study 2) primarily sampled for the analysis of Borrelia spp. or Mycoplasma pneumoniae. Sixteen of these patients were seroreactive for Rickettsia spp., of which five were judged as recent or current infection. Symptoms of arthritis, fever, cough and rash were predominant. In 80 blood donors without clinical symptoms, approximately 1 % were seroreactive for Rickettsia spp., interpreted as past infection. The study shows that both single and co-infections do occur, which illustrate the complexity in the clinical picture and a need for further studies to fully understand how these patients should best be treated.

T-cell epitope mapping of the Borrelia garinii outer surface protein A in lyme neuroborreliosis

We studied the T-cell reactivity to overlapping peptides of B. garinii OspA, in order to locate possible immunodominant T-cell epitopes in neuroborreliosis. Cells from cerebrospinal fluid (CSF) and blood from 39 patients with neuroborreliosis and 31 controls were stimulated with 31 overlapping peptides, and interferon-gamma secreting cells were detected by ELISPOT. The peptides OspA(17-36), OspA(49-68), OspA(105-124), OspA(137-156), OspA(193-212) and OspA(233-252) showed the highest frequency of positive responses, being positive in CSF from 38% to 50% of patients with neuroborreliosis. These peptides also elicited higher responses in CSF compared with controls (P = 0.004). CSF cells more often showed positive responses to these peptides than blood cells (P = 0.001), in line with a compartmentalization to the central nervous system. Thus, a set of potential T-cell epitopes were identified in CSF cells from patients with neuroborreliosis. Further studies may reveal whether these epitopes can be used diagnostically and studies involving HLA interactions may show their possible pathogenetic importance.

Brain magnetic resonance imaging does not contribute to the diagnosis of chronic neuroborreliosis

BACKGROUND

Borrelia infections, especially chronic neuroborreliosis (NB), may cause considerable diagnostic problems. This diagnosis is based on symptoms and findings in the cerebrospinal fluid but is not always conclusive.

PURPOSE

To evaluate brain magnetic resonance imaging (MRI) in chronic NB, to compare the findings with healthy controls, and to correlate MRI findings with disease duration.

MATERIAL AND METHODS

Sixteen well-characterized patients with chronic NB and 16 matched controls were examined in a 1.5T scanner with a standard head coil. T1- (with and without gadolinium), T2-, and diffusion-weighted imaging plus fluid-attenuated inversion recovery (FLAIR) imaging were used.

RESULTS

White matter lesions and lesions in the basal ganglia were seen in 12 patients and 10 controls (no significant difference). Subependymal lesions were detected in patients down to the age of 25 and in the controls down to the age of 43. The number of lesions was correlated to age both in patients (rho = 0.83, P<0.01) and in controls (rho = 0.61, P<0.05), but not to the duration of disease. Most lesions were detected with FLAIR, but many also with T2-weighted imaging.

CONCLUSION

A number of MRI findings were detected in patients with chronic NB, although the findings were unspecific when compared with matched controls and did not correlate with disease duration. However, subependymal lesions may constitute a potential finding in chronic NB.

Decreased up-regulation of the interleukin-12Rbeta2-chain and interferon-gamma secretion and increased number of forkhead box P3-expressing cells in patients with a history of chronic Lyme borreliosis compared with asymptomatic Borrelia-exposed individuals

Lyme borreliosis (LB) can, despite adequate antibiotic treatment, develop into a chronic condition with persisting symptoms such as musculoskeletal pain, subjective alteration of cognition and fatigue. The mechanism behind this is unclear, but it has been postulated that an aberrant immunological response might be the cause. In this study we investigated the expression of the T helper 1 (Th1) marker interleukin (IL)-12Rbeta2, the marker for T regulatory cells, forkhead box P3 (FoxP3) and the cytokine profile in patients with a history of chronic LB, subacute LB, previously Borrelia-exposed asymptomatic individuals and healthy controls. Fifty-four individuals (12 chronic LB, 14 subacute LB, 14 asymptomatic individuals and 14 healthy controls) were included in the study and provided a blood sample. Mononuclear cells were separated from the blood and stimulated with antigens. The IL-12Rbeta2 and FoxP3 mRNA expression was analysed with real-time reverse transcription-polymerase chain reaction (RT-PCR). The protein expression of IL-12Rbeta2 on CD3(+), CD4(+), CD8(+) and CD56(+) cells was assessed by flow cytometry. Furthermore, the secretion of interferon (IFN)-gamma, IL-4, IL-5, IL-10, IL-12p70 and IL-13 was analysed by enzyme-linked immunospot (ELISPOT) and/or enzyme-linked immunosorbent assay (ELISA). Chronic LB patients displayed a lower expression of Borrelia-specific IL-12Rbeta2 on CD8(+) cells and also a lower number of Borrelia-specific IFN-gamma-secreting cells compared to asymptomatic individuals. Furthermore, chronic LB patients had higher amounts of Borrelia-specific FoxP3 mRNA than healthy controls. We speculate that this may indicate that a strong Th1 response is of importance for a positive outcome of a Borrelia infection. In addition, regulatory T cells might also play a role, by immunosuppression, in the development of chronic LB.

Janus computerised prescribing system provides pharmacological knowledge at point of care - design, development and proof of concept

OBJECTIVE

To develop and verify proof of concept for a user-defined prescribing system with decision support based on one single database consisting of several pharmacological sources.

METHODS

A multidisciplinary working group within the framework of a two-phase project developed the tool. A small-scale pilot study for proof of concept was carried out in an outpatient neurological polyclinic where four experienced physicians used the tool in patient care on a daily basis.

RESULTS

Automatically generated functions, such as recommended drugs, alerts for interactions, alerts for drug therapy during pregnancy and breast-feeding and a search tool for adverse drug effects, were quickly adopted into the daily outpatient working regime. Functions such as treatment strategies and a link to a producer independent website were less frequently used but still rated as useful and educational.

CONCLUSION

Searches for information that can be concentrated in one system saves time. Alerts inevitably draw physicians' attention to the information. Instant availability to drug recommendations in a computerised prescribing system such as Janus should increase adherence to recommendations, but this needs to be evaluated systematically. Small-scale pilot studies such as the one reported here have been shown to be invaluable in providing the theoretical basis for implementation of the system and for gaining an understanding of the complex change processes involved. Small-scale projects can therefore provided a base for further development and broader implementation of pharmacological tools and services.

Reduced number of interleukin-12 secreting cells in patients with Lyme borreliosis previously exposed to Anaplasma phagocytophilum

Lyme borreliosis and human granulocytic ehrlichiosis are tick-borne diseases caused by Borrelia burgdorferi and Anaplasma phagocytophilum, respectively. Infection with A. phagocytophilum has been observed to induce immunosuppression and animal studies suggest that the bacteria might also have prolonged inhibitory effects on immune cells. The aim of this study was to investigate the cytokine secretion in patients exposed previously to A. phagocytophilum and currently infected with B. burgdorferi compared with patients infected with B. burgdorferi and seronegative for A. phagocytophilum. Eight patients with erythema migrans and antibodies against A. phagocytophilum, 15 patients with erythema migrans and negative A. phagocytophilum serology and 15 non-exposed healthy individuals were included in the study. Blood mononuclear cells were stimulated with Borrelia-antigen and the number of cytokine [interleukin (IL)-4, IL-5, IL-12, IL-13 and interferon (IFN)-gamma]-secreting cells was detected by enzyme-linked immunospot (ELISPOT). This study shows that patients with a previous exposure to A. phagocytophilum and a current infection with B. burgdorferi have a lower number of Borrelia-specific cells secreting IL-12 compared to Ap seronegative patients infected with B. burgdorferi (P < 0.001), indicating impairment in the ability to mount strong Th1-responses. We suggest that this mirrors a reduced Th1 response caused by A. phagocytophilum which could influence the outcome of the Borrelia infection and, speculatively, may also have implications in other conditions.

Innate immune responses in Lyme borreliosis: enhanced tumour necrosis factor-alpha and interleukin-12 in asymptomatic individuals in response to live spirochetes

Innate immunity is important for early defence against borrelia spirochetes and should play a role in the clinical outcome of the infection. In order to study early cytokine responses, in vitro differentiated dendritic cells (DCs) and whole blood cells from 21 patients with different clinical outcomes of Lyme neuroborreliosis were stimulated with live borrelia spirochetes. The borrelia-induced secretion of interleukin (IL)-4, IL-10, IL-12p70, interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha in DCs and IL-1beta, IL-6, IL-8, IL-10, IL-12p70, TNF-alpha, regulated upon activation normal T cell expressed and secreted (RANTES), monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and eotaxin in whole blood cells was measured by enzyme-linked immunospot (ELISPOT) and multiplex arrays, respectively. We found increased numbers of TNF-alpha-secreting DCs (P = 0.018) in asymptomatic seropositive individuals compared to patients with subacute neuroborreliosis and seronegative controls. Asymptomatic individuals were also found to have elevated levels of IL-12p70 (P = 0.031) in whole blood cell supernatants compared to seronegative controls. These results are in line with previous experiments using cells of the adaptive immune response, indicating that strong T helper type 1 (Th1) proinflammatory responses might be associated with a successful resolution of Lyme disease.

Lyme borreliosis in Sweden--diagnostic performance of five commercial Borrelia serology kits using sera from well-defined patient groups

Five commercial Borrelia serology kits available in Sweden were evaluated and compared for their diagnostic performance in sera from clinically well-characterized patient groups. With the clinically defined groups as the gold standard, i.e. without knowledge of antibody status in serum and cerebrospinal fluid, the diagnostic performance of the kits was compared and important differences in diagnostic usefulness were found. The kits from Abbot and DAKO, that often predict clinically relevant Borrelia infection and do not detect antibodies in sera from patients without strong suspicion of Borrelia infection, were considered the most useful in the population studied. This kind of validation study is an important part of good laboratory practice and should be performed by laboratories serving patient populations with varying endemicity of Borrelia.

Phenotypes indicating cytolytic properties of Borrelia-specific interferon-gamma secreting cells in chronic Lyme neuroborreliosis

The immuno-pathogenetic mechanisms underlying chronic Lyme neuroborreliosis are mainly unknown. Human Borrelia burgdorferi (Bb) infection is associated with Bb-specific secretion of interferon-gamma (IFN-gamma), which may be important for the elimination of Bb, but this may also cause tissue injury. In order to increase the understanding of the pathogenic mechanisms in chronic neuroborreliosis, we investigated which cell types that secrete IFN-gamma. Blood mononuclear cells from 13 patients with neuroborreliosis and/or acrodermatitis chronicum atrophicans were stimulated with Bb antigen and the phenotypes of the induced IFN-gamma-secreting cells were analyzed with three different approaches. Cells expressing CD8 or TCRgammadelta, which both have cytolytic properties, were the main phenotypes of IFN-gamma-secreting cells, indicating that tissue injury in chronic neuroborreliosis may be mediated by cytotoxic cells.

Chronic symptoms are common in patients with neuroborreliosis -- a questionnaire follow-up study

OBJECTIVES

The existence of chronic neuroborreliosis is controversial. The aim of our study was to investigate the existence and kind of persistent symptoms in patients previously treated because of neurological symptoms as a result of neuroborreliosis.

MATERIALS AND METHODS

A total of 106 patients with neuroborreliosis, according to established criteria, and a control group of 123 patients with Borrelia induced erythema migrans diagnosed in a general practitioner office were studied. A questionnaire was sent to patients and controls concerning their health situation. Time from onset of neurological symptoms to the questionnaire send out was 32 months (mean) for the patients with neuroborreliosis and 33 months (mean) for the controls.

RESULTS

Fifty per cent of the individuals in the patient group compared with 16% of the individuals in the control group showed persistent complaints after their Borrelia infection (P < 0.0001). The most significant differences between the groups were the presence of neuropsychiatric symptoms such as headache, attention problems, memory difficulties and depression. Paresthesia, pain and persistent facial palsy was also significantly more common in patients treated because of neuroborreliosis.

CONCLUSION

Our study shows that persisting neurological symptoms are common after a neuroborreliosis infection. The pathological mechanisms that lay behind the development of chronic symptoms, however, are still uncertain.

High serum hepatocyte growth factor levels in the acute stage of community-acquired infectious diseases

Acute serum levels of hepatocyte growth factor (HGF) were studied in 6 clinical groups with (i) gastroenteritis, (ii) skin and soft tissue infection, (iii) urinary tract infection, (iv) septicemia, (v) influenza, and (vi) chronic hepatitis C in comparison with a normal control group using an enzyme-linked immunosorbent assay method. We found that serum HGF levels were significantly higher in patients with acute infectious diseases (p < 0.0001) compared to patients with chronic viral hepatitis and healthy controls. Serum HGF and CRP levels were correlated significantly (r=0.65, p < 10(-7)). We conclude that serum HGF levels are elevated in patients with acute infectious diseases.

Hepatocyte growth factor may accelerate healing in chronic leg ulcers: a pilot study

BACKGROUND

Hepatocyte growth factor (HGF) is a heparin-binding protein with mitogenic, motogenic and morphogenic activities for various cell types. The regenerative properties of HGF have been the object of several animal and in vitro studies in recent years.

OBJECTIVE

To investigate the physiological and therapeutic effects of HGF on chronic leg ulcers.

METHODS

HGF in gel form was locally applied, once daily for 7 days, to 15 of 19 chronic leg ulcers in 11 elderly patients. All patients had previously been treated by conventional methods and their leg ulcers had been in stable conditions for between 1 and 14 years. Any signs of allergy, discomfort or pain were reported daily. Microcirculation perfusion in the ulcers, compared to the intact contiguous skin, was determined by laser Doppler at the beginning of the study, after 1 week and again after 3 months (in seven patients). Ulcer size and characteristics were also documented.

RESULTS

It was observed that microcirculatory perfusion, which might reflect the angiogenic effect of HGF, was statistically significantly correlated (r = 0.94, p < 0.002) to ulcer area reduction in the treated ulcers. Excellent (84-100% area reduction) or partial healing (58-59%) was seen in eight out of 11 patients. No control group was included in this pilot study, which must be completed by proper control studies.

CONCLUSION

This study suggests that HGF may heal chronic leg ulcers, possibly by improving the microcirculation. Proper control studies need to be performed.

Antibodies and T-cell reactivity to Borrelia burgdorferi in an asymptomatic population: a study of healthy blood donors in an inland town district in the south-east of Sweden

To address the issue of whether Borrelia infection can be asymptomatic, blood donors with no history of borreliosis (n = 408) were screened for antibodies against Borrelia burgdorferi. Seropositive individuals (n = 17) were further investigated with respect to Borrelia-specific T-cell reactivity, using an interferon-gamma ELISPOT assay. Anti-Borrelia antibodies as well as Borrelia-specific T-cell responses were evident in 9 asymptomatic donors, strongly supporting a current or previous asymptomatic Borrelia infection.

Exhaled breath condensate and serum levels of hepatocyte growth factor in pneumonia

Hepatocyte growth factor (HGF) is a protein produced by mesenchymal cells in many organs, which can stimulate epithelial growth. An enhanced production and concentration of HGF is observed after injuries. The lung is one of the major sources of HGF. By cooling exhaled air, a condensate is formed containing molecules from bronchi and alveoli. In order to investigate HGF-concentration and time course in pneumonia, paired serum and exhaled breath condensate was collected from 10 patients with pneumonia, 10 patients with non-respiratory infections and 11 healthy controls. The concentration of HGF was measured by an immunoassay kit. In the acute phase HGF-levels in breath condensate and serum were significantly higher in the patients with pneumonia compared to the control groups. Similar concentrations in breath condensate were seen in healthy controls and in patients with non-respiratory infections. In the patients with pneumonia a decrease in serum HGF was seen already after 4-7 days while HGF values in breath condensate remained elevated even after 4-6 weeks. These results might imply local product on of HGF in the lungs and a long repair and healing process after pneumonia.

A comparison of brain, core and skin temperature in children with complicated and uncomplicated malaria

A prospective study was carried out in which brain, core and skin temperatures were studied in children with cerebral malaria (n = 23), uncomplicated malaria (n = 12) and normal children (n = 9) using the zero heat flow method. Patients with cerebral or uncomplicated malaria were admitted to the paediatric wards (mean age, 6 years 8 months +/- 2 years 8 months). Normal children, children of the investigators, of the same age group, served as controls. Parasitaemia levels were similar in the cerebral and uncomplicated malaria cases. Higher brain than core temperatures would have been expected in cerebral malaria but not in uncomplicated malaria but this was not the case in this study. There was no statistical difference in brain, core and skin temperature between cerebral and uncomplicated malaria patients. However, there was a highly significant difference between normal children and cerebral and uncomplicated malaria patients. Brain temperature was 0.02-0.2 degrees C below core temperature in all the groups with larger differences during the febrile period. Mean differences of brain minus core, brain minus skin and core minus skin between the two groups of patients were not statistically significant. There was no correlation between temperature and the level of coma or parasitaemia for cerebral and uncomplicated malaria patients. There was a positive correlation between brain and core temperature in both groups of patients during the febrile phase. Brain temperature remained lower than core temperature in cerebral and uncomplicated malaria as in normal children. Normal thermoregulation appears to be maintained in cerebral malaria.

Hepatocyte growth factor levels in cerebrospinal fluid: a comparison between acute bacterial and nonbacterial meningitis

The organotrophic functions of the hepatocyte growth factor (HGF) have been the subject of several studies. In the more recent studies, this function has been reported in the brain. In the present study, we have measured the levels of HGF in cerebrospinal fluid (CSF) and sera from 78 patients divided into 6 different groups according to central nervous system (CNS) infection and control. Quantitative measurements of HGF in the CSF and serum were performed by an enzyme-linked immunosorbent assay. Elevated values of CSF HGF were found in the patients with acute bacterial/probable bacterial meningitis (P<.001), compared with nonbacterial CNS infections and facial palsy, as well as with a control group without signs of CNS involvement. The values of CSF HGF were not correlated to blood-brain-barrier disruption in the groups. These observations might indicate an intrathecal production of HGF in acute bacterial/probable bacterial meningitis.

Asymptomatic Borrelia-seropositive individuals display the same incidence of Borrelia-specific interferon-gamma (IFN-gamma)-secreting cells in blood as patients with clinical Borrelia infection

Borrelia Lyme disease is a complex disorder that sometimes becomes chronic. There are contradictory reports of experimental Borrelia infections regarding which type of T cell cytokine responses, i.e. Th1 or Th2, are needed to eradicate the Borrelia spirochaetes. In human borreliosis a predominance of Borrelia-specific Th1-like responses has been shown. In this study, spontaneous, as well as Borrelia-specific, secretion of IFN-gamma (Th1) and IL-4 (Th2) in Borrelia-seropositive healthy asymptomatic individuals (n = 17) was investigated in peripheral blood by a sensitive ELISPOT assay, and compared with previously reported responses in patients with clinical Borrelia infection (n = 25). The seropositive asymptomatic individuals displayed the same predominance of Borrelia-specific IFN-gamma-secreting cells as the patients with clinical Borrelia infection. Interestingly, the proportion of spontaneously IL-4-secreting cells, reflecting the unstimulated in vivo secretion, was lower in the seropositive asymptomatic individuals compared with patients with chronic Borrelia infections (n = 13, P = 0.02), whereas no such difference was found compared with subacute Borrelia infections (n = 12). These findings indicate that IFN-gamma secretion alone is not sufficient to eliminate Borrelia spirochaetes in humans, although IFN-gamma may still have a beneficial role in borreliosis acting in concert with other mechanisms.

Clinical presentation and diagnosis of cerebral malaria in children in the highlands of western Kenya

BACKGROUND

The clinical presentation of cerebral malaria in children in the highlands has not been documented.

OBJECTIVE

To describe the presentation of cerebral malaria in the age group one to twelve years.

DESIGN

Prospective study conducted from May to September 1997, the rainy season during which malaria occurs in epidemics in the highlands of Kenya.

SETTING

Paediatric wards of the Moi Teaching and Referral Hospital, Eldoret which is the Teaching Hospital for Moi University and the referral centre for surrounding districts of Western Kenya, with an altitude of over 2000 metres above sea level.

PATIENTS

Twenty three consecutive children aged one to twelve years with cerebral malaria as defined by the WHO were studied. All children were treated with the standard quinine regimen for cerebral malaria.

RESULTS

Majority of the children were six to ten years of age with 95.7% having a normal weight for age. 91.3%, 89.5% and 72.2% had fever, headache and convulsions respectively. 68.1% had a short duration of illness (less than three days) with only 9.5% presenting with hypoglycaemia. Severe anaemia was not observed but 72% had mild to moderate anaemia. Hyperparasitaemia (parasite counts greater than 100,000 per microlitre) was found in majority of the cases.

CONCLUSION

Cerebral malaria presentation in the highlands is similar to that among non-immune populations and is an acute fulminant illness presenting with coma, hyperparasitaemia, fever and convulsions in children with normal nutritional status.

Augmented intrathecal secretion of interferon-gamma in response to Borrelia garinii in neuroborreliosis

The Lyme disease agent Borrelia garinii has been suggested to be neurotrop, preferentially affecting the nervous system. We compared the secretion of interferon-gamma in response to outer surface proteins from Borrelia garinii and Borrelia afzelii in 10 patients with neuroborreliosis. In cerebrospinal fluid, stimulation with Borrelia garinii revealed higher numbers of interferon-gamma-secreting cells in all patients, whereas in blood, only five displayed higher numbers. This further strengthens the hypothesis of Borrelia garinii being associated with the development of neuroborreliosis.

IgG subclasses in Lyme borreliosis: a study of specific IgG subclass distribution in an interferon-gamma-predominated disease

Lyme borreliosis has shown a T helper type 1 (Th1)-like immune response with high production of interferon-gamma. Since the cytokine environment seems to be important in the regulation of immunoglobulin production and in the switch between different isotypes and subclasses, and since the subclasses of IgG have different functions, we wanted to examine the IgG subclass distribution in Lyme borreliosis. We have developed an ELISA measuring flagellin-specific antibodies of the different IgG subclasses in serum and cerebrospinal fluid (CSF). Thirty-five seropositive patients with varying manifestations of Lyme borreliosis were included in the study. According to the results, the predominating subclasses in both serum and CSF were IgG1 and IgG3. In samples taken early in disease this pattern was more pronounced in patients with a subacute disease, defined as recovery within 3 months, compared to patients that later on developed chronic borreliosis. The levels of IgG2 were generally low and IgG4 was below detection level. Thus, in the IFN-gamma-predominated immune response seen in Lyme borreliosis, mainly IgG1 and IgG3 were found, i.e. the subclasses that are complement activating as well as opsonizing in humans. Increased levels of these two subclasses early in disease might contribute to recovery and counteract the development of chronicity. The absence of IgG4 is in accordance with the presumed Th1-like situation of Lyme borreliosis.

CD4 and CD8 lymphocyte subsets in cerebrospinal fluid and peripheral blood from patients with multiple sclerosis, meningitis and normal controls

OBJECTIVES

To study the distribution of CD4+ and CD8+ T-cell subsets in cerebrospinal fluid (CSF) and peripheral blood from patients with multiple sclerosis (MS), meningitis, other neurological diseases and healthy controls.

MATERIAL AND METHODS

The expression of markers for naive and memory cells (CD45RA+ and CD45R0+), and helper/inducer cells (CD29+) on CD4+ cells as well as CD45R0+ and killer/effector (S6F1+) on CD8+ cells was investigated in cerebrospinal fluid (CSF) and peripheral blood from patients with multiple sclerosis (n=28), meningitis (n=13), other neurological diseases (n=16), and healthy controls (n=16) by 2-color flow cytometry.

RESULTS

The majority of T cells in the CSF of the 4 groups exhibited the phenotype of memory cells (CD45R0+) on both CD4+ and CD8+ cells. The proportion of helper/inducer (CD29+CD4+ in CD4+) cells was also larger in the CSF compared to peripheral blood in the 3 patient groups and controls investigated. In contrast, CD8+ cells with killer/effector (S6F1+) phenotype were fewer in CSF compared to peripheral blood in all 4 groups. There were no significant differences between patients and controls regarding the distribution of these activation markers in the CSF or peripheral blood.

CONCLUSION

Our observations support the notion that activated T cells of both CD4+ and CD8+ phenotype selectively pass the blood-brain barrier under both pathological and normal conditions.

Problem-based medical education: development of a theoretical foundation and a science-based professional attitude

Problem-based learning, combined with early patient contact, integration between different subject areas, elements of multiprofessional education, and special emphasis on the development of communications skills has become the basis for the medical curriculum at the Faculty of Health Sciences in Linköping. Critics have questioned the depth of the scientific and theoretical aspects of the curriculum. Through a series of specific measures in the organization of the curriculum and examinations, and due to the pedagogical principles involved per se, our claim is that students graduating at Linköping do possess the required theoretical knowledge and a scientific attitude to the practice of medicine, at least equivalent to that obtained in a more conventional medical curriculum. One such specific measure is that all students perform one field study and two scientific studies during the course of the curriculum. An investigation of student opinions regarding the value of performing scientific projects of their own have shown that these projects have had a positive impact on the students' general scientific attitude and their willingness to engage in future scientific work. The specific skills acquired, as confirmed by oral examinations, were largely determined by the scientific nature of the chosen field of study. Our graduates have not yet progressed far enough in their careers for comparisons to be made on the basis of the Swedish Licensing Board Internship Examinations, but continuing evaluations of students, graduates and licensed doctors emerging from the curriculum will provide future evidence as to whether our present evaluation is correct.

Compartmentalization of antigen specific cytokine responses to the central nervous system in CNS borreliosis: secretion of IFN-gamma predominates over IL-4 secretion in response to outer surface proteins of Lyme disease Borrelia spirochetes

The neurological manifestations of Lyme disease have been proposed to be partly due to cytokine-mediated immunopathological mechanisms. In this study, the number of Borrelia-specific cells secreting interferon-gamma and interleukin-4 was determined in blood and cerebrospinal fluid from patients with CNS borreliosis (n = 23), other neurological diseases (n = 20), and in blood from healthy controls (n = 10), utilizing an ELISPOT-assay. Elevated specific secretion of IFN-gamma was found in CNS borreliosis, most pronounced in cerebrospinal fluid, whereas secretion of IL-4 was strikingly low. This may indicate that symptoms are due to side effects of the immune response, since IFN-gamma secretion in the absence of corresponding levels of IL-4 may be associated with tissue destruction.

Determination of total and herpes simplex virus specific monomeric and dimeric IgA in serum and cerebrospinal fluid by ultracentrifugation

An improved method is described for differentiating between monomeric and dimeric total and herpes simplex virus (HSV) specific IgA by ultracentrifugation in sucrose gradient, using recovery and quantitative analysis of the fractions obtained. Calculation of monomeric and dimeric IgA was based on IgG as an internal standard. Intrathecally produced monomeric and dimeric IgA were judged by calculating IgA indices for each form. A new type of formula indicating relative over-production of dimeric compared with monomeric IgG (IgA dimeric-monomeric index) is suggested. The method was applied to serum and cerebrospinal fluid (CSF) from three patients with HSV encephalitis. The index for monomeric as well as dimeric IgA was high during the acute phase of the disease, indicating intrathecal synthesis of both molecular forms. One year after onset, there was no detectable HSV-specific IgA in CSF: both molecular forms, however, remained in serum. The amount of dimeric compared with monomeric IgA was high during the acute phase, and subsequently decreased after successful treatment. A new finding was the detection of HSV-specific IgA heavier than dimeric IgA in serum one year after onset of the disease. These components may be tetrameric IgA, or immune complexes containing IgA.

The outer surface proteins of Lyme disease borrelia spirochetes stimulate T cells to secrete interferon-gamma (IFN-gamma): diagnostic and pathogenic implications

Late stages of borrelia Lyme disease infections may be difficult to diagnose because of unspecific symptoms and unreliable laboratory tests, being too unspecific or insensitive. The T cell immune response was thus evaluated in these patients by using a sensitive ELISPOT T cell assay that detects the secretion of IFN-gamma, i.e. a T helper 1 (Th1) response on the single-cell level. Three subcellular fractions of the Lyme borreliosis strain Borrelia afzelii were used for antigenic stimulation. The outer surface protein (Osp) fraction elicited the strongest response, discriminating between borrelia infections (n = 15) compared with other neurological diseases (n = 10) and normal controls (n = 12) (P = 0.0001). The more heterogeneous sonicated borrelia fraction also elicited a strong response, however, also in some of the controls. The flagellin fraction did not have a similar T cell-stimulating effect. When looking at subgroups of borrelia infections, central nervous system (CNS) infections (n = 7) revealed a lower T cell response in blood (P = 0.0128) compared with other borrelia manifestations (n = 8). Cerebrospinal fluid (CSF) lymphocytes were available from three patients with CNS borreliosis, and all showed a compartmentalization with higher responses to the Osp fraction in CSF compared with blood, also in the two patients without any intrathecal-specific antibody synthesis. The ELISPOT method is feasible for detecting a specific IFN-gamma T cell response in borrelia infections. This Th1 response may well be of pathogenic relevance.

Intrathecal production of specific IgA antibodies in CNS infections

Cerebrospinal fluid (CSF) and serum from subjects with herpes simplex encephalitis, herpes zoster, mumps meningitis and neuroborreliosis were analysed for the presence of immunoglobulin A (IgA) and G (IgG) antibodies to the corresponding four antigens. Specific intrathecal IgA antibody synthesis as manifested by an elevated index was a frequent finding. Higher IgA index values than the corresponding IgG was seen in one third of the samples from subjects with herpes simplex encephalitis and herpes zoster. Correlation between specific IgG and IgA index was most pronounced for varicella-zoster virus (r = 0.66, P < 0.001). In subjects with mumps meningitis a strong intrathecal IgA and IgG antibody response to Borrelia burgdorferi was demonstrated. Specific herpes simplex and varicella-zoster virus IgA was not found to contain secretory component, thus contradicting an active secretion into the CNS compartment. In conclusion, our data indicate that specific IgA is intrathecally produced in herpes simplex encephalitis, herpes zoster and mumps meningitis but is a rare finding in neuroborreliosis.

Lower values for immunoglobulin M in cerebrospinal fluid when sampled with an atraumatic Sprotte needle compared with conventional lumbar puncture

Immunoglobulin M (IgM) has a very low concentration in cerebrospinal fluid (CSF) compared with serum, and therefore determinations of IgM in CSF are highly sensitive to pre-analytical errors caused by contamination with serum or interstitial fluid. Capillary attraction causes a thin layer of liquid containing serum proteins to be formed inside a conventional (Quincke) needle during penetration of tissue. To investigate this source of pre-analytical error, 35 patients had lumbar punctures using a 22 G atraumatic (Sprotte) or 25 G conventional (Quincke) needle according to a randomized scheme, and the IgM concentrations in CSF and serum were determined. The CSF IgM concentrations for samples taken with a Sprotte needle were significantly lower than those taken with a Quincke needle (P < 0.05), whereas the corresponding serum IgM concentrations and CSF erythrocyte counts did not differ significantly. The difference indicates that CSF IgM concentrations determined after conventional sampling may be falsely increased by contamination. We conclude that IgM concentrations in CSF samples taken with the atraumatic technique are more accurate, and recommend the use of this technique when CSF IgM is to be determined.

Long-term findings in patients with facial palsy and antibodies against Borrelia burgdorferi

Little is known about the long-term effects of Borrelia burgdorferi (Bb) infection in untreated patients with peripheral facial palsy. We investigated 12 patients with elevated serum Bb antibody levels, with a median follow-up time of 11 years, during which 3 of the 12 still exhibited intrathecal antibody production of antibodies against Bb flagellar antigen, and 2 of the 3 had normal serum Bb antibodies. Four of the 12 had elevated serum antibody titres at the late follow-up examination. Arthralgia, reported by 7 patients, was the single most common complaint. Four patients showed extensive oculomotor disturbances, which were not correlated to antibody titres or intrathecal antibody synthesis. In 1 of the patients with intrathecal Bb antibody production, most symptoms were eradicated by antibiotic treatment 6 years after the initial infection. We conclude that even several years after a Bb infection, intrathecal Bb antibody production can still occur in serum Bb IgG antibody negative patients with a history of facial palsy.

Improved formulae for the judgement of intrathecally produced IgA and IgM in the presence of blood CSF barrier damage

In order to discriminate between transsudated and intrathecally produced IgA and IgM in patients with blood cerebrospinal fluid (CSF) barrier (BCB) damage, we developed extended indices (IgA-EI and IgM-EI) for these immunoglobulins according to the general formula for extended index of a component X in CSF: X-EI = (CSF-X/serum-X)/(CSF-albumin/serum-albumin)a where a is a parameter specific for X. For IgA parameter a was found to be 1.15 and for IgM 1.9. A preliminary evaluation of IgA-EI and IgM-EI indicated lower false positive rates as compared to CSF IgA and IgM concentrations as well as 'conventional' IgA and IgM indices in cases with BCB damage, and essentially the same rates as for the hyperbolic formulae of Reiber and Felgenhauer. The importance of reliable sampling and analytical technique for IgM in CSF is discussed.