Lactate dehydrogenase and hemolysis index to predict vaso-occlusive crisis in sickle cell disease

Sickle cell disease (SCD) is an inherited hemoglobinopathy disorder associated with chronic hemolysis. A major complication is vaso-occlusive crisis (VOC), associating frequent hospitalization, morbidity and mortality. The aim of this study was to investigate whether hemolysis biomarkers were able to predict VOC risk in adult patients with SCD requiring hospitalization within 1 year. This single-center prospective study included adult patients with SCD at steady state or during VOC. A total of 182 patients with SCD were included, 151 at steady state and 31 during VOC. Among the 151 patients at steady state 41 experienced VOC within 1 year (median: 3.0 months [2.0-6.5]). We observed an increase of lactate dehydrogenase (LDH) (p = 0.01) and hemolysis index (HI) (p = 0.0043) during VOC compared to steady state. Regarding patients with VOC requiring hospitalization, LDH (p = 0.0073) and HI (p = 0.04) were increased. In unadjusted logistic regression, LDH > median (> 260 U/L) (RR = 3.6 [1.29-10.88], p = 0.0098) and HI > median (> 8 UA/L) (RR = 3.13 [1.91-5.33]; p < 0.001) were associated with VOC. The association of LDH > 260 U/L and HI > 12 UA/L presented a sensitivity of 90%, and a specificity of 72.9% to predict VOC. The association of LDH and HI cut-off was able to predict VOC risk in SCD.

High prevalence of pre-existing sarcopenia in critically ill patients with hematologic malignancies admitted to the intensive care unit for sepsis or septic shock

BACKGROUND & AIMS

We aimed to evaluate body composition (BC) by computed tomography (CT) in hematologic malignancy (HM) patients admitted to the intensive care unit (ICU) for sepsis or septic shock.

METHODS

We retrospectively assessed BC and its impact on outcome of 186 patients at the 3rd lumbar (L3) and 12th thoracic vertebral levels (T12) using CT-scan performed before ICU admission.

RESULTS

The median patient age was 58.0 [47; 69] years. Patients displayed adverse clinical characteristics at admission with median [q1; q3] SAPS II and SOFA scores of 52 [40; 66] and 8 [5; 12], respectively. The mortality rate in the ICU was 45.7%. Overall survival rates at 1 month after admission in the pre-existing sarcopenic vs. non pre-existing sarcopenic patients were 47.9% (95% CI [37.6; 61.0]) and 55.0% (95% CI [41.6; 72.8]), p = 0.99), respectively, at the L3 level and 48.4% (95% CI [40.4; 58.0]) vs. 66.7% (95% CI [51.1; 87.0]), p = 0.062), respectively, at the T12 level.

CONCLUSIONS

Sarcopenia is assessable by CT scan at both the T12 and L3 levels and is highly prevalent in HM patients admitted to the ICU for severe infections. Sarcopenia may contribute to the high mortality rate in the ICU in this population.

Case report: CAR-T cell therapy-induced cardiac tamponade

CD19-specific chimeric antigen receptor T (CAR-T) cell therapy has recently been shown to improve the prognosis of refractory diffuse large B-cell lymphoma (DLBCL). However, CAR-T cells may induce numerous adverse events, in particular cytokine release syndrome (CRS) which is frequently associated with cardiovascular manifestations. Among the latter, acute pericardial effusion represents less than 1% of cases and cardiac tamponade has only been reported once. The management and outcome of these severe complications are not well established. We report here, a case of cardiac tamponade associated with CRS in a context of CAR-T cell therapy, which required urgent pericardiocentesis.

Case summary

A 65-year-old man with refractory DLBCL was treated with CAR-T cell therapy. He had a history of dilated cardiomyopathy with preserved ejection fraction and transient atrial fibrillation. A pericardial localization of the lymphoma was observed on the second relapse. One day after CAR-T cell infusion the patient was diagnosed with grade 1 CRS. Due to hypotension, he was treated with tocilizumab and dexamethasone, and then transferred to intensive care unit (ICU). Echocardiography performed at ICU admission showed acute pericardial effusion with signs of right ventricular heart failure due to cardiac tamponade. It was decided to perform pericardiocentesis despite grade IV thrombocytopenia in a context of aplasia. Analysis of pericardial fluid showed a large number of lymphoma cells and 73% of CAR-T cells amongst lymphocytes, a level that was similar in blood. Hemodynamic status improved after pericardiocentesis, and no recurrence of pericardial effusion was observed. The presence of a high count of activated CAR-T cells in the pericardial fluid as well as the short interval between CAR-T cells injection and the symptoms appear as potential arguments for a direct action of CAR-T cells in the mechanism of this adverse event. The patient was discharged from ICU after two days and initially exhibited a good response to DLBCL treatment. Unfortunately, he died fifty days after starting CAR-T cell therapy due to a new DLBCL relapse.

Conclusion

Patients with a pericardial localization of DLBCL should be assessed for a risk of cardiac tamponade if receiving CAR-T cell therapy and presenting CRS. In this case, cardiac tamponade seems directly related to CAR-T cell expansion. Pericardiocentesis should be considered as a feasible and effective treatment if the risk of bleeding is well controlled, in association with anti-IL6 and corticosteroids.

Post-traumatic stress disorder and quality of life alterations in survivors of immune-mediated thrombotic thrombocytopenic purpura and atypical hemolytic and uremic syndrome

Thrombotic thrombocytopenic purpura (iTTP) and atypical hemolytic-uremic syndrome (aHUS), once in remission, may cause long-term symptoms, among which mental-health impairments may be difficult to detect. We conducted telephone interviews 72 [48-84] months after ICU discharge to assess symptoms of anxiety, depression, and posttraumatic stress disorder (PTSD) and the 36-item Short Form questionnaire (SF-36). Of 103 included patients, 52 had iTTP and 51 aHUS; 74% were female, median age was 39 y (31-54), and 39 (38%) patients were still taking treatment. Symptoms of anxiety, PTSD and depression were present in 50%, 27% and 14% of patients, respectively, with no significant difference between the iTTP and aHUS groups. Patients with PTSD symptoms had significantly greater weight gain and significantly worse perceived physical and/or emotional wellbeing, anxiety symptoms, and depression symptoms. The SF-36 physical and mental components indicated significantly greater quality-of-life impairments in patients with vs. without PTSD symptoms and in those with aHUS and PTSD vs. iTTP with or without PTSD. In the aHUS group, quality of life was significantly better in patients with vs. without eculizumab treatment. Factors independently associated with PTSD symptoms were male sex (odds ratio [OR], 0.11; 95%CI, 0.02-0.53), platelet count ≤20 G/L at acute-episode presentation (OR, 2.68; 1.01-7.38), and current treatment (OR, 2.69; 95%CI, 1.01-7.36). Mental-health screening should be routine in patients with iTTP and aHUS to ensure appropriate care.

Investigation of thrombin generation assay to predict vaso-occlusive crisis in adulthood with sickle cell disease

Introduction

Sickle cell disease (SCD) is an inherited hemoglobinopathy disorder. The main consequence is synthesis of hemoglobin S leading to chronic hemolysis associated with morbidity. The aim of this study was to investigate Thrombin Generation Assay (TGA) to assess hypercoagulability in SCD and TGA parameters as biomarkers of vaso-occlusive crisis (VOC) risk and hospitalization within 1 year.

Materials and methods

We performed TGA in platelet poor plasma (PPP) with 1 pM of tissue factor and 4 μM of phospholipid-standardized concentration, in duplicate for patients and controls. We measured thrombomodulin (TM), soluble endothelial Protein C Receptor and Tissue Factor Pathway Inhibitor (TFPI).

Results

A total of 113 adult patients with SCD, 83 at steady state and 30 during VOC, and 25 healthy controls matched on age and gender were included. Among the 83 patients at steady state, (36 S/S-1 S/β⁰, 20 S/Sα³.⁷, and 19 S/C-7 S/β⁺) 28 developed a VOC within 1 year (median: 4 months [2.25–6]). We observed an increase of peak and velocity associated with a shortening of lagtime and time to peak (TTP) and no difference of endogenous thrombin potential (ETP) in patients compared to controls. TFPI (p < 0.001) and TM (p = 0.006) were significantly decreased. TGA confirmed hypercoagulability in all SCD genotypes and clinical status. The association of ETP > 1,207 nM.min and peak >228.5 nM presented a sensitivity of 73.5% and a specificity of 93.9% to predict VOC development within 1 year.

Conclusion

We have demonstrated a hypercoagulable state in SCD associated with chronic hemolysis. These preliminary findings suggest that TGA parameters, as ETP and peak, could be used to predict VOC development within 1 year.

Assessment of Reticulocyte and Erythrocyte Parameters From Automated Blood Counts in Vaso-Occlusive Crisis on Sickle Cell Disease

Sickle cell disease is a complex genetic disease involving cell adhesion between red blood cells, white blood cells, platelets and endothelial cells, inducing painful vaso-occlusive crisis (VOC). We assessed reticulocyte and erythrocyte parameters in a cohort of confirmed SCD patients, and investigated whether a combination of these routine laboratory biomarkers of haemolysis could be used to predict VOC development. Reticulocyte and erythrocyte parameters were evaluated using the Sysmex XN-9000 analyser. A total of 98 patients with SCD were included, 72 in steady state and 26 in VOC. Among the 72 patients in steady state, 22 developed a VOC in the following year (median: 3 months [2-6]). The following parameters were increased in SCD patients with VOC development compared to SCD patients without VOC development in the following year: reticulocyte count (94.6 10⁹/L [67.8-128] vs. 48.4 10⁹/L [24.9-87.5]), immature reticulocyte count (259 10⁹/L [181-334] vs. 152 10⁹/L [129-208]) reticulocyte/immature reticulocyte fraction (IRF) ratio (6.63 10⁹/(L^*%) [4.67-9.56] vs. 4.94 10⁹/(L^*%) [3.96-6.61]), and medium fluorescence reticulocytes (MFR) (19.9% [17.4-20.7] vs. 17.1% [15.95-19.75]). The association of a reticulocyte count of >189.4 10⁹/L and an MFR of >19.75% showed a sensitivity of 81.8% and a specificity of 88% to predict VOC development in the following year. Based on our findings, a combination of routine laboratory biomarkers, as reticulocyte count, immature reticulocyte count and fluorescent reticulocyte fraction at steady state, could be used to predict VOC development in SCD.

Characteristics of thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly syndrome: a retrospective study from a large Western cohort

Idiopathic multicentric Castleman disease (iMCD) is a non-clonal inflammatory lymphoproliferative disorder of unknown origin. Recently, TAFRO syndrome (thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly) emerged as a singular variant of iMCD in Asia and was associated with a severe course and a poor outcome. The present study describes the first large Western cohort of TAFRO syndrome patients (n = 25) meeting the All Japan TAFRO Syndrome Research Group diagnostic criteria. Characteristics of TAFRO patients were compared to iMCD-not otherwise specified (iMCD-NOS) patients used as a control group (n = 43). Our results show that despite baseline characteristics in accordance with previously reported series, Western TAFRO syndrome patients do not appear to present with a worse outcome than iMCD-NOS patients. There were no significant differences between the two groups regarding treatment choice, response to rituximab (71% vs. 67%) or tocilizumab (69% vs. 91%) in TAFRO and iMCD-NOS, respectively. The two-year overall survival was above 95% in both groups. Limits of inclusion and exclusion criteria for TAFRO definition are also discussed. Our findings raise the question of the singularity of the TAFRO entity in Western countries. The data should promote further research using unsupervised models to identify markers of disease severity in Western cohorts of iMCD patients.

Eculizumab in gemcitabine-induced thrombotic microangiopathy: experience of the French thrombotic microangiopathies reference centre

BACKGROUND

Gemcitabine is a broadly prescribed chemotherapy, the use of which can be limited by renal adverse events, including thrombotic microangiopathy (TMA).

METHODS

This study evaluated the efficacy of eculizumab, a monoclonal antibody targeting the terminal complement pathway, in patients with gemcitabine-induced TMA (G-TMA). We conducted an observational, retrospective, multicenter study in 5 French centres, between 2011 and 2016.

RESULTS

Twelve patients with a G-TMA treated by eculizumab were included. The main characteristics were acute renal failure (100%), including stage 3 acute kidney injury (AKI, 58%) and renal replacement therapy (17%), hypertension (92%) and diffuse oedema (83%). Eculizumab was started after a median of 15 days (range 4-44) following TMA diagnosis. A median of 4 injections of eculizumab was performed (range 2-22). Complete hematological remission was achieved in 10 patients (83%) and blood transfusion significantly decreased after only one injection of eculizumab (median of 3 packed red blood cells (range 0-10) before treatment vs 0 (range 0-1) after one injection, P < 0.001). Two patients recovered completely renal function (17%), and 8 achieved a partial remission (67%). Compared to a control group of G-TMA without use of eculizumab, renal outcome was more favourable. At the end of the follow up, median eGFR was 45 vs 33 ml/min/1.73m2 respectively in the eculizumab group and in the control group.

CONCLUSIONS

These results suggest that eculizumab is efficient on haemolysis and reduces transfusion requirement in G-TMA. Moreover, eculizumab may improve renal function recovery.

Systematic screening for a proximal DVT in COVID-19 hospitalized patients: Results of a comparative study

INTRODUCTION

The COVID-19 pandemic is associated with a high incidence of venous thromboembolism questioning the utility of a systematic screening for deep venous thrombosis (DVT) in hospitalised patients.

METHODS

In this prospective bicentric controlled study, 4-point ultrasound using a pocket device was used to screen for DVT, in patients with SARS-CoV-2 infection and controls admitted for acute medical illness not related to COVID-19 hospitalised in general ward, in order to assess the utility of a routine screening and to estimate the prevalence of VTE among those patients.

RESULTS

Between April and May 2020, 135 patients were screened, 69 in the COVID+ group and 66 in the control one. There was no significant difference in the rate of proximal DVT between the two groups (2.2% vs. 1.5%; P=0.52), despite the high rate of PE diagnosed among COVID-19 infected patients (10.1% vs. 1.5%, P=0.063). No isolated DVT was detected, 37.5% of PE was associated with DVT. Mortality (7.2% vs. 1.5%) was not different (P=0.21) between COVID-19 patients and controls.

CONCLUSION

The systematic screening for proximal DVT was not found to be relevant among COVID-19 patients hospitalized in general ward despite the increase of VTE among this population. Further studies are needed to confirm the hypothesis of a local pulmonary thrombosis which may lead to new therapeutic targets.

A Rare Case of Henoch-Schönlein Purpura and Mycobacterium xenopi Pulmonary Infection

Henoch-Schönlein purpura (HSP) is a small-vessel vasculitis with cutaneous, articular, gastrointestinal, and renal manifestations. Leukocytoclastic vasculitis and IgA deposits are classically found when involved skin and kidneys are biopsied. The disease's etiology remains unknown, although many bacterial and viral infections have been described as triggering factors.

A 53-year-old woman presented with fever, arthralgia, and non-thrombocytopenic purpura. She also had a segmental pulmonary collection with peripheral alveolar consolidation. Staphylococcus aureus and mycobacteria growth was found on sputum cultures. In addition to intravenous antibiotics and anti-mycotic drugs, high-dose corticosteroids were urgently administered due to the development of severe intestinal symptoms. A cutaneous biopsy later confirmed HSP. Microbial identification yielded Mycobacterium xenopi.

In the review of the literature, we only found 12 cases of Mycobacterium tuberculosis and one case of Mycobacterium avium-intracellulare complex that were associated with HSP. Nearly, half of the cases responded to anti-mycotic treatment alone. The rest required immunosuppressants. 

We report the first case of M. xenopi pulmonary infection in HSP. This disease process can have a severe course, which requires rapid recognition and treatment.

Severe leptospirosis in non-tropical areas: a nationwide, multicentre, retrospective study in French ICUs

PURPOSE

To report the incidence, risk factors, clinical presentation, and outcome predictors of severe leptospirosis requiring intensive care unit (ICU) admission in a temperate zone.

METHODS

LEPTOREA was a retrospective multicentre study conducted in 79 ICUs in metropolitan France. Consecutive adults admitted to the ICU for proven severe leptospirosis from January 2012 to September 2016 were included. Multiple correspondence analysis (MCA) and hierarchical classification on principal components (HCPC) were performed to distinguish different clinical phenotypes.

RESULTS

The 160 included patients (0.04% of all ICU admissions) had median values of 54 years [38-65] for age, 40 [28-58] for the SAPSII, and 11 [8-14] for the SOFA score. Hospital mortality was 9% and was associated with older age; worse SOFA score and early need for endotracheal ventilation and/or renal replacement therapy; chronic alcohol abuse and worse hepatic dysfunction; confusion; and higher leucocyte count. Four phenotypes were identified: moderately severe leptospirosis (n = 34, 21%) with less organ failure and better outcomes; hepato-renal leptospirosis (n = 101, 63%) with prominent liver and kidney dysfunction; neurological leptospirosis (n = 8, 5%) with the most severe organ failures and highest mortality; and respiratory leptospirosis (n = 17, 11%) with pulmonary haemorrhage. The main risk factors for leptospirosis contamination were contact with animals, contact with river or lake water, and specific occupations.

CONCLUSIONS

Severe leptospirosis was an uncommon reason for ICU admission in metropolitan France and carried a lower mortality rate than expected based on the high severity and organ-failure scores. The identification in our population of several clinical presentations may help clinicians establish an appropriate index of suspicion for severe leptospirosis.

[Pre-hospitalization unit: A simple organization and a place for internists to improve the non-scheduled hospitalization stream from emergencies]

INTRODUCTION

The adult emergency department at Rouen University hospital (CHU) welcomes over 100.000 patients per year. In order to streamline unscheduled hospital admissions from the emergency room (ER), a 20-bed pre-hospitalization unit and a centralized bed management system (bed manager, bed manager software, dedicated beds) have been put into place.

PATIENTS AND METHODS

Emergency admissions have increased by (+3.5% between 2017 and 2018) with 20% direct hospitalization from the ER to other conventional units (2/3 in medicine, 1/3 in surgery). In 2018, 3450 patients, of which 54% aged over 75 years have been admitted in the pre-hospitalization unit with an average length of stay of 1.3±1.4 days: 35.4% stayed less than 24hours and 34.8% more than 48hours of which 5.2% stated more than 4 days, 132 patients (3.8%) died, 805 patients (23.3%) were discharged at home, 220 (6.4%) transferred to another facility, and 2287 (66.3%) were secondarily hospitalized in another hospital unit: more than 9 times out of 10 in a medicine unit (internal medicine 30%, geriatrics 27.9%, respiratory medicine 12.2%). This unscheduled emergency hospitalization allowed a daily hospitalization of 50 short stay inpatients beds. It has to be noted that the number of available inpatient beds clearly decreases during the week-ends. The main pathologies were respiratory infections (14.2%), heart diseases (9.7%), metabolic disorders (3.9%), and urinary tract infections (13.6%).

CONCLUSION

This pre-hospitalization unit associated with a centralized bed management system has clearly improved the unscheduled hospital admissions, in particular concerning the emergency medical sector. The lack of inpatient beds at the week-end and the management of epidemic periods still remain a challenge that has to be taken up.

Clinical features and outcome of patients with acute respiratory failure revealing anti-synthetase or anti-MDA-5 dermato-pulmonary syndrome: a French multicenter retrospective study

Background

Anti-synthetase (AS) and dermato-pulmonary associated with anti-MDA-5 antibodies (aMDA-5) syndromes are near one of the other autoimmune inflammatory myopathies potentially responsible for severe acute interstitial lung disease. We undertook a 13-year retrospective multicenter study in 35 French ICUs in order to describe the clinical presentation and the outcome of patients admitted to the ICU for acute respiratory failure (ARF) revealing AS or aMDA-5 syndromes.

Results

From 2005 to 2017, 47 patients (23 males; median age 60 [1st–3rd quartiles 52–69] years, no comorbidity 85%) were admitted to the ICU for ARF revealing AS (n = 28, 60%) or aMDA-5 (n = 19, 40%) syndromes. Muscular, articular and cutaneous manifestations occurred in 11 patients (23%), 14 (30%) and 20 (43%) patients, respectively. Seventeen of them (36%) had no extra-pulmonary manifestations. C-reactive protein was increased (139 [40–208] mg/L), whereas procalcitonine was not (0.30 [0.12–0.56] ng/mL). Proportion of patients with creatine kinase ≥ 2N was 20% (n = 9/47). Forty-two patients (89%) had ARDS, which was severe in 86%, with a rate of 17% (n = 8/47) of extra-corporeal membrane oxygenation requirement. Proportion of patients who received corticosteroids, cyclophosphamide, rituximab, intravenous immunoglobulins and plasma exchange were 100%, 72%, 15%, 21% and 17%, respectively. ICU and hospital mortality rates were 45% (n = 21/47) and 51% (n = 24/47), respectively. Patients with aMDA-5 dermato-pulmonary syndrome had a higher hospital mortality than those with AS syndrome (n = 16/19, 84% vs. n = 8/28, 29%; p = 0.001).

Conclusions

Intensivists should consider inflammatory myopathies as a cause of ARF of unknown origin. Extra-pulmonary manifestations are commonly lacking. Mortality is high, especially in aMDA-5 dermato-pulmonary syndrome.

Thrombotic thrombocytopenic purpura misdiagnosed as autoimmune cytopenia: Causes of diagnostic errors and consequence on outcome. Experience of the French thrombotic microangiopathies reference centre

Thrombotic thrombocytopenic purpura (TTP) has a devastating prognosis without adapted management. Sources of misdiagnosis need to be identified to avoid delayed treatment. We studied 84 patients with a final diagnosis of severe (<10%) acquired ADAMTS13 deficiency-associated TTP from our National database that included 423 patients, who had an initial misdiagnosis (20% of all TTP). Main diagnostic errors were attributed to autoimmune thrombocytopenia, associated (51%) or not (37%) with autoimmune hemolytic anemia. At admission, misdiagnosed patients were more frequently females (P = .034) with a history of autoimmune disorder (P = .017) and had organ involvement in 67% of cases; they had more frequently antinuclear antibodies (P = .035), a low/undetectable schistocyte count (P = .001), a less profound anemia (P = .008), and a positive direct antiglobulin test (DAT) (P = .008). In multivariate analysis, female gender (P = .022), hemoglobin level (P = .028), a positive DAT (P = .004), and a low schistocytes count on diagnosis (P < .001) were retained as risk factors of misdiagnosis. Platelet count recovery was significantly longer in the misdiagnosed group (P = .041) without consequence on mortality, exacerbation and relapse. However, patients in the misdiagnosed group had a less severe disease than those in the accurately diagnosed group, as evidenced by less organ involvement at TTP diagnosis (P = .006). TTP is frequently misdiagnosed with autoimmune cytopenias. A low schistocyte count and a positive DAT should not systematically rule out TTP, especially when associated with organ failure.

Identification and purification of glucose phosphate isomerase of Plasmodium falciparum

The multiplication of malaria parasites within red blood cells is energy dependent. Since these parasites lack a functional tricarboxylic acid cycle, the energy needs of the parasite are met by anaerobic glycolysis of exogenous glucose. High levels of glycolytic enzymes such as fructose-1,6-diphosphate aldolase, phosphoglycerate kinase and pyruvate kinase have been detected in infected erythrocytes. Here we report a 4-9 times increase in glucose phosphate isomerase (GPI) activity of infected erythrocytes over that of normal erythrocytes. This increase is of parasitic origin, as additional enzyme bands were observed in lysates of infected erythrocytes. The expression of GPI parallels parasite maturation and reaches a maximum at the trophozoite/schizont stage. Two distinct but closely related activity patterns consisting of 3-4 GPI isoenzymes (not shown in normal erythrocytes) with neutral to weakly acidic isoelectric points were observed in 6 P. falciparum isolates tested by isoelectric focusing. The purified P. falciparum GPI has an apparent size of 66 kDa. No size variation was observed in the 6 P. falciparum isolates studied. Furthermore, antiserum raised against this protein in BALB/c mice specifically inhibits parasite encoded GPI activity while no effect was observed on host enzyme activity.

Plasmodium falciparum: identification and purification of the phosphoglycerate kinase of the malaria parasite

Multiplication of the human malaria parasite Plasmodium falciparum within red blood cells is an energy-dependent process and glucose consumption increases dramatically in infected red blood cells (IRBC) versus normal red blood cells (NRBC). The major pathway for glucose metabolism in P. falciparum IRBC is anaerobic glycolysis. Phosphoglycerate kinase (PGK) is one of the key enzymes of this pathway as it generates ATP. We found that the PGK specific activity in P. falciparum IRBC is seven times higher than that in NRBC. The parasitic origin of the increase in PGK activity is confirmed by isoelectric focusing. Indeed, two P. falciparum isoenzymes with neutral isoelectric points were detected. P. falciparum PGK in purified form has a molecular mass of 48 kDa. Antiserum raised against purified P. falciparum PGK specifically recognizes the 48-kDa protein band in P. falciparum and also reacts with P. berghei and P. yoelii IRBC lysates but does not cross-react with PGK associated with NRBC.

Comparative evaluation of an ELISA based on recombinant polypeptides and IFA for serology of malaria

In the present investigation we compare the performance of a solid-phase assay based on three recombinant polypeptides corresponding to three asexual blood-stage antigens of P. falciparum (ELISA MIXT) with the reference method for the measurement of antimalaria antibodies: indirect immunofluorescence antibody assay (IFA). Sera collected from persons with various degrees of exposure to malaria were selected: sera from inhabitants of a malaria endemic area (Group I), European patients with acute malaria infection (Group II) and blood donors with clinical symptoms of sickness or fever during a stay in malaria endemic areas. 86% of the sera gave concording results by ELISA MIXT and IFA. The correlation was 100% for sera of Group I but discrepancies were observed for Groups II and III. The great majority of the differences were due to sera positive on ELISA MIXT but not by IFA. Most of the sera positive on ELISA MIXT reacted with parasite-derived components only on Western-blot. These results underline the potential of the ELISA MIXT for epidemiologic studies.

[Unilateral renal atrophy]

The authors report 45 cases of unilateral renal atrophy. The circumstances of discovery are related to the urological symptoms: pain, hematuria, pyuria. On the other hand, hypertension is rarely the reason for consultation. Women are more affected than men. Intravenous urography, retrograde cystography and arteriography are essential examinations to collect information concerning the etiology. Dynamic scintiscanning with measurement of the percentage of isotope fixed on the kidneys, has the advantage of permitting comparative evaluation of renal function on each side. In our study, obstruction of the urinary tract was more frequent than parenchymatous disease favoured by infection. Vascular abnormalities were rare. The etiological enquiry remained, however, negative in one third of cases. Surgical operation was necessary when a urological abnormality was the cause of persistence of severe symptoms. On the other hand, removal of the atrophic kidney does not seem to us advisable when decided simply to relieve hypertension. The latter point is particularly discussed.