Course of Plasmodium infection studied using 2D-COS on human erythrocytes.

BACKGROUND: The threat of malaria is still present in the world. Recognizing the type of parasite is important in determining a treatment plan. The golden routine involves microscopic diagnostics of Giemsa-stained thin blood smears, however, alternative methods are also constantly being sought, in order to gain an additional insight into the course of the disease. Spectroscopic methods, e.g., Raman spectroscopy, are becoming increasingly popular, due to the non-destructive nature of these techniques. METHODS: The study included patients hospitalized for malaria caused by Plasmodium falciparum or Plasmodium vivax, in the Department of Infectious Diseases at the University Hospital in Krakow, Poland, as well as healthy volunteers. The aim of this study was to assess the possibility of using Raman spectroscopy and 2D correlation (2D-COS) spectroscopy in understanding the structural changes in erythrocytes depending on the type of attacking parasite. EPR spectroscopy and two-trace two-dimensional (2T2D) correlation was also used to examine the specificity of paramagnetic centres found in the infected human blood. RESULTS: Two-dimensional (2D) correlation spectroscopy facilitates the identification of the hidden relationship, allowing for the discrimination of Raman spectra obtained during the course of disease in human red blood cells, infected by P. falciparum or P. vivax. Synchronous cross-peaks indicate the processes taking place inside the erythrocyte during the export of the parasite protein towards the cell membrane. In contrast, moieties that generate asynchronous 2D cross-peaks are characteristic of the respective ligand-receptor domains. These changes observed during the course of the infection, have different dynamics for P. falciparum and P. vivax, as indicated by the asynchronous correlation cross-peaks. Two-trace two-dimensional (2T2D) spectroscopy, applied to EPR spectra of blood at the beginning of the infection, showed differences between P. falciparum and P. vivax. CONCLUSIONS: A unique feature of 2D-COS is the ability to discriminate the collected Raman and EPR spectra. The changes observed during the course of a malaria infection have different dynamics for P. falciparum and P. vivax, indicated by the reverse sequence of events. For each type of parasite, a specific recycling process for iron was observed in the infected blood.

Mortality review as a tool to assess the contribution of healthcare-associated infections to death: results of a multicentre validity and reproducibility study, 11 European Union countries, 2017 to 2018.

IntroductionThe contribution of healthcare-associated infections (HAI) to mortality can be estimated using statistical methods, but mortality review (MR) is better suited for routine use in clinical settings. The European Centre for Disease Prevention and Control recently introduced MR into its HAI surveillance.AimWe evaluate validity and reproducibility of three MR measures.MethodsThe on-site investigator, usually an infection prevention and control doctor, and the clinician in charge of the patient independently reviewed records of deceased patients with bloodstream infection (BSI), pneumonia, Clostridioides difficile infection (CDI) or surgical site infection (SSI), and assessed the contribution to death using 3CAT: definitely/possibly/no contribution to death; WHOCAT: sole cause/part of causal sequence but not sufficient on its own/contributory cause but unrelated to condition causing death/no contribution, based on the World Health Organization's death certificate; QUANT: Likert scale: 0 (no contribution) to 10 (definitely cause of death). Inter-rater reliability was assessed with weighted kappa (wk) and intra-cluster correlation coefficient (ICC). Reviewers rated the fit of the measures.ResultsFrom 2017 to 2018, 24 hospitals (11 countries) recorded 291 cases: 87 BSI, 113 pneumonia , 71 CDI and 20 SSI. The inter-rater reliability was: 3CAT wk 0.68 (95% confidence interval (CI): 0.61-0.75); WHOCAT wk 0.65 (95% CI: 0.58-0.73); QUANT ICC 0.76 (95% CI: 0.71-0.81). Inter-rater reliability ranged from 0.72 for pneumonia to 0.52 for CDI. All three measures fitted 'reasonably' or 'well' in > 88%.ConclusionFeasibility, validity and reproducibility of these MR measures was acceptable for use in HAI surveillance.

Neurological symptoms in hospitalised patients with COVID-19 and their association with in-hospital mortality.

OBJECTIVES: To evaluate the spectrum of neurological symptoms in patients with COVID-19 during the first 14 days of hospitalisation and its association with in-hospital mortality. MATERIAL AND METHODS: We included 200 patients with RT-PCR-confirmed COVID-19 admitted to University Hospital in Krakow, Poland. In 164 patients, a detailed questionnaire concerning neurological symptoms and signs was performed prospectively within 14 days of hospitalisation. In the remaining 36 patients, such questionnaires were completed retrospectively based on daily observations in the Department of Neurology. RESULTS: During hospitalisation, 169 patients (84.5%) experienced neurological symptoms; the most common were: fatigue (62.5%), decreased mood (45.5%), myalgia (43.5%), and muscle weakness (42.5%). Patients who died during hospitalisation compared to the remainder were older (79 [70.5-88.5] vs. 63.5 [51-77] years, p = 0.001), and more often had decreased level of consciousness (50.0% vs. 9.3%, p < 0.001), delirium (33.3% vs. 4.4%, p < 0.001), arterial hypotension (50.0% vs. 19.6%, p = 0.005) or stroke during (18.8% vs. 3.3%, p = 0.026) or before hospitalisation (50.0% vs. 7.1, p < 0.001), whereas those who survived more often suffered from headache (42.1% vs. 0%, p = 0.012) or decreased mood (51.7% vs. 0%, p = 0.003). CONCLUSIONS: Most hospitalised patients with COVID-19 experience neurological symptoms. Decreased level of consciousness, delirium, arterial hypotension, and stroke during or before hospitalisation increase the risk of in-hospital mortality.

A multicenter retrospective study of 223 patients with t(14;16) in multiple myeloma.

The t(14;16) translocation, found in 3%-5% of newly diagnosed (ND) multiple myeloma (MM), has been associated with adverse outcomes. However, the studies establishing the characteristics of t(14;16) included solely small cohorts. The goal of the current international, multicenter (n = 25 centers), retrospective study was to describe the characteristics and outcomes of t(14;16) patients in a large, real-world cohort (n = 223). A substantial fraction of patients had renal impairment (24%) and hemoglobin <10 g/dL (56%) on initial presentation. Combined therapy of both immunomodulatory drug and proteasome inhibitor (PI) in the first line was used in 35% of patients. Autologous stem cell transplantation was performed in 42% of patients. With a median follow up of 4.1 years (95% CI 3.7-18.7), the median progression-free survival (PFS) and overall survival (OS) from first line therapy were 2.1 years (95% CI 1.5-2.4) and 4.1 years (95% CI 3.3-5.5), respectively. Worse OS was predicted by age > 60 years (HR = 1.65, 95% CI [1.05-2.58]), as well as revised International Scoring System (R-ISS) 3 (vs R-ISS 2; HR = 2.59, 95% CI [1.59-4.24]). In conclusion, based on the largest reported cohort of t(14;16) patients, quarter of this subset of MM patients initially presents with renal failure, while older age and the R-ISS 3 predict poor survival.

Clostridium difficile infection: review.

Clostridium difficile (C. difficile) is a Gram-positive, spore-forming, anaerobic bacillus, which is widely distributed in the intestinal tract of humans and animals and in the environment. In the last decade, the frequency and severity of C. difficile infection has been increasing worldwide to become one of the most common hospital-acquired infections. Transmission of this pathogen occurs by the fecal-oral route and the most important risk factors include antibiotic therapy, old age, and hospital or nursing home stay. The clinical picture is diverse and ranges from asymptomatic carrier status, through various degrees of diarrhea, to the most severe, life threatening colitis resulting with death. Diagnosis is based on direct detection of C. difficile toxins in feces, most commonly with the use of EIA assay, but no single test is suitable as a stand-alone test confirming CDI. Antibiotics of choice are vancomycin, fidaxomicin, and metronidazole, though metronidazole is considered as inferior. The goal of this review is to update physicians on current scientific knowledge of C. difficile infection, focusing also on fecal microbiota transplantation which is a promising therapy.

Fatty acids and selected endocannabinoids content in cerebrospinal fluids from patients with neuroinfections.

Neuroinfections are a significant medical problem and can have serious health consequences for patients. Their outcome, if not fatal, can be associated with permanent residual deficits. Cerebrospinal fluid (CSF) examination is commonly used for meningitis confirmation. Fatty acids (FA) are precursors of lipid mediators with pharmacological activity. They actively modulate inflammation as well as contribute to its resolution. Therefore the aim of this study was to determine the FA and selected endocannabinoids (ECB) content in the CSF obtained from patients with bacterial (BM) and viral meningitis (VM) using chromatographic techniques. A significantly lower level of saturated FA was found in patients with BM and VM as compared to controls. There was a significantly higher concentration of long-chain monounsaturated FA and polyunsaturated n-6 FA in the CSF obtained from patients with neuroinfection. Moreover, a significant reduction of n-3 FA in CSF obtained from patients with BM and VM was demonstrated. The highest amount of ECB was detected in the CSF of patients with VM: eicosapentaenoyl ethanolamide (1.65 pg/mL), docosahexaenoyl ethanolamide (655.5 pg/mL) and nervonoyl ethanolamide (3.09 ng/mL). Results indicate the participation of long-chain monounsaturated and polyunsaturated FA and their derivatives in the inflammatory process and likely in the process of resolution of inflammation during neuroinfection. It seems that the determination of the FA and ECB profile in CSF may be a valuable biomarker of health and may allow the development of new pharmacological strategies, therapeutic goals and fatty acids supplementation necessary in the fight against inflammation of the central nervous system.

Meningoencephalitis caused by Lactobacillus plantarum - case report.

Specific strains of Lactobacillus spp. are widely used as probiotic agents but it has been repeatedly reported that may have a pathogenic potential. We present the report on a case of meningoencephalitis caused by Lactobacillus plantarum in a 63-year-old man with newly diagnosed metastatic planoepitheliale lung cancer. The patient was hospitalised due to newly diagnosed cancer and during the course of hospitalisation developed symptoms of neuroinfection. On the basis of the symptoms and results of the conducted tests the patient was diagnosed with bacterial meningoencephalitis. In microbiological tests of the blood and cerebrospinal fluid L. plantarum was cultured. During the course of antibiotic therapy the patient's condition improved. Lactobacilli are now recognised as a causative agent of infection, most notably bacteraemia. To our knowledge, this is the fourth documented case of Lactobacillus-associated neuroinfection, and only the second in an adult. Lactobacilli cause mostly opportunistic infections in immunocompromised individuals.

Differences between palpation and static/dynamic tests to diagnose painful temporomandibular disorders in patients with Lyme disease.

OBJECTIVES: The aim was to determine the frequency of Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD)-based pain diagnoses and dynamic/static tests-based pain diagnoses, and to assess the agreement of palpation tests with static/dynamic tests. MATERIALS AND METHODS: Eighty-six (N = 86) adult patients with Lyme disease (mean age 57.0 ± 14.3 years; male/female ratio was 42/44) were examined according to techniques described in the RDC/TMD. Additionally, dynamic/static tests were performed. For RDC/TMD-based pain diagnoses and dynamic/static tests-based pain diagnoses, descriptive frequencies were calculated. Differences between the frequency of palpation-based diagnoses and of dynamic/static-based diagnoses as well as the agreement between pain diagnoses established with the two diagnostic approaches were assessed. RESULTS: RDC/TMD-based pain diagnoses were made in 61 patients for myofascial pain and in 11 patients for arthralgia and/or osteoarthritis. Based on dynamic/static tests, mainly myogenous pain was diagnosed in 6 patients, and a mainly arthrogenous pain in 5. The agreement of palpation tests with static/dynamic tests in Lyme disease population was poor. CONCLUSION: A high prevalence of TMD symptoms was found in patients with Lyme disease. The results suggest that using palpation tests alone could overestimate primary TMDs when comorbid conditions are present. CLINICAL RELEVANCE: Dynamic/static tests should be used as part of the routine TMD assessment. In case of Lyme disease as the actual cause of the facial pain, while the dentist might be suspecting TMD when dynamic/static TMD tests are negative, referral to an appropriate specialist for the diagnosis and treatment of Lyme disease needs to be made.

Analysis of cases of Lyme arthritis in patients hospitalized in Infectious Diseases Department, University Hospital in Cracow.

Lyme disease is an emerging problem in Poland. Analysis has been undertaken of the medical documentation of 86 patients hospitalized in the Infectious Diseases Department, University Hospital in Cracow in 2013-2016, suspected of Lyme arthritis. It has especially considered medical history including potential exposure to the infection, detailed characteristics of the symptoms, diagnostic challenges and results of the treatment. Only some patients had a history of erythema migrans and not all of them recalled tick-bite. The majority of the patients had affected large joints, especially knee joints, and polyarthritis was rarely observed. Symptoms were resolved completely or partially after antibiotic treatment in most patients. The diagnosis of Lyme arthritis in areas endemic for Lyme disease is still a diagnostic challenge in patients with other rheumatic diseases, including osteoarthritis.

The level of fecal calprotectin significantly correlates with Clostridium difficile infection severity.

INTRODUCTION: Fecal calprotectin (FC) rises significantly in intestinal inflammation accompanied by neutrophil activation - such as Clostridium difficile infection (CDI). The aim of the study was to evaluate the benefit of FC testing in assessing the severity of CDI. MATERIALS AND METHODS: The study group included 76 patients with CDI hospitalized in the Jagiellonian University Hospital in Krakow from July 2017 till January 2018. FC levels were measured using an EIA (Enzyme Immunoassay). Demographic, clinical information and blood tests were recorded using standardized data collection forms. The selection of patients into non-severe and severe groups was carried out in accordance with the ESCMID criteria (European Society of Clinical Microbiology and Infectious Diseases) and some modi cations to those criteria were proposed. RESULTS: the studied population included 76 patients (39 men and 37 women) with CDI aged from 24 to 98 years (mean: 72). Median calprotectin level was 739 (Q25-Q75: 612-799 µg/g), characteristic of patients with colitis. A statistically significant difference in FC concentration in patients with severe vs non-severe CDI was observed (severe - 770 vs non-severe - 659 µg/g, p = 0.009). FC directly correlated with platelets level; however, no correlation between FC level and the blood parameters prognostic for CDI (leukocyte, neutrophil count, albumin, creatinine levels) was found. CONCLUSION: FC level is an indication of ongoing intestinal inflammation in CDI patients. FC level significantly correlated with CDI severity, which demonstrates that FC could serve as a predictive marker for assessing CDI severity.

The presence of IL-8 +781 T/C polymorphism is associated with the parameters of severe Clostridium difficile infection.

PURPOSE: There is large variation in the clinical manifestations of Clostridium difficile infection (CDI). We also still can not predict which patients are more susceptible to reinfection with CDI. The aim of our study was to evaluate the effect of gene single nucleotide polymorphisms (SNP) of proinflammatory cytokines, specifically IL-1ß, IL-8 on the development, clinical course and recurrence of CDI. METHODS: We performed a prospective study of adults (130 people ≥ 18 years) including 65 patients with CDI treated in tertiary hospital and 65 healthy persons. The following 3 variants were analyzed for the occurrence of gene polymorphisms in patients with CDI versus the control group: IL-1ß +3953 A/G (rs1143634), IL-1ß -31 A/G (rs1143627), and IL-8 +781 T/C (rs2227306). Then, we assessed the correlation between these genetic polymorphisms and biochemical parameters important in CDI course, CDI severity as well as CDI recurrence. RESULTS AND CONCLUSIONS: The presence of genetic polymorphisms of IL-1ß +3953 A/G, -31 A/G and IL-8 +781 T/C did not have an effect on the development or recurrence of CDI. The presence of IL-8 +781 T/C polymorphism is associated with the severe CDI.

Analysis of risk factors and outcomes of Clostridium difficile infection.

INTRODUCTION: Clostridium difficile (C. difficile) is a Gram-positive, anaerobic rod-shaped bacteria, widely spread in the human environment. In the last decade, the frequency and severity of Clostridium difficile infection (CDI) have been increasing, making this particular disease one of the most significant nosocomial infections. The aim of our study was an analysis of CDI risk factors, its course and consequences. MATERIALS AND METHODS: Medical documentation of the patients treated for CDI in the University Hospital in Cracow and St Anne's Hospital in Miechów has been analysed. The analysis focused on epidemiological data, blood parameters, comorbidities, recurrence rate, and complication rate (deaths included). As part of risk factors analysis, antibiotic use or hospitalisation in a period of 3 months before the episode of infection was considered relevant. Blood tests have been performed using routinely employed, standard methods. RESULTS: We evaluated data of 168 people infected with C. difficile, out of which there were 102 women (61%) and 66 men (39%). The median age of the patients was 74 years for the entire population with 76 years for women and 71 years for male patients. One hundred thirteen people (67%) had been previously hospitalised, and 5 person was a pensioner of a nursing home. 99 people (59%) were treated with antibiotics within 3 months before the first episode of infection. An average length of the hospital stay because of CDI was 11 days. One hundred thirty persons (77%) experienced only 1 episode whereas 38 people (23%) had more than 1 episode of infection. The person with the largest number of recurrences had 9 of them. CONCLUSIONS: The development of CDI is an increasing problem in a group of hospitalised persons, particularly of an old age. The general use of beta-lactam antibiotics is the cause of a larger number of infections with C. difficile. Vast majority of patients have had at least one typical risk factor of CDI.

Clostridium difficile infection in young people - 2 case reports.

Clostridium difficile infection (CDI) remains one of the most important healthcare-associated infections of the last two decades. The pathogen is a Gram-positive, toxin-producing, anaerobic, rod-shaped and sporeforming bacterium; it is ubiquitous in the human environment. Transmission occurs by the fecal-oral route. The consequence of the action of bacterial toxins is initially a local inflammatory reaction, which then goes into systemic inflammation. Clinical presentation is varied; some patients are asymptomatic, in symptomatic form the main symptom is diarrhea of varying severity, which is sometimes accompanied by acute abdominal pain, nausea, vomiting and high fever. Risk factors of CDI include prior antibiotic use, increasing age and recent hospitalisation. Extremely rarely does CDI occur in immunocompetent patients under 30 years of age, even if previously treated with an antibiotic. Here presented are two untypical cases of CDI development in the lower age group, in the presence of additional risk factors of comorbid gastrointestinal tract infections. Both developed infections are following recent infection - Salmonella enterididis in the first case and Salmonella typhi in the second case. Therefore, the article also contains basic principles for the diagnosis and treatment of Salmonella spp.

Similar survival outcomes in patients with biclonal versus monoclonal myeloma: a multi-institutional matched case-control study.

Multiple myeloma is a plasma cell malignancy characterized by clonal proliferation of plasma cells in the bone marrow and associated organ damage. Usually, patients with myeloma present with a single monoclonal protein in serum and/or urine constituted by one heavy chain and one light chain. In less than 5% of the patients, more than one monoclonal protein can be identified. The aim of our retrospective multicenter matched case-control study was to describe the characteristics of cases with biclonal myeloma and compare them against a control group of monoclonal myeloma patients matched by age, sex, and year of diagnosis. A total of 50 previously untreated cases with biclonal myeloma and 50 matched controls with monoclonal myeloma were included in this study. The controls were matched (1:1) for age, sex, year of diagnosis, and participating center. There were no differences in the rates of anemia (52 vs. 59%; p = 0.52), renal dysfunction (36 vs. 34%; p = 0.83), hypercalcemia (9 vs. 16%; p = 0.28), or presence of lytic lesions (23 vs. 16%; p = 0.38) between groups. Similarly, there was no difference in the rates of overall response to therapy (85 vs. 90%; p = 0.88) or survival rates of cases with biclonal myeloma and controls with monoclonal myeloma (4-year survival 72 vs. 76%; p = 0.23). Results of our study suggest that patients with biclonal myeloma have similar response and survival rates than patients with monoclonal myeloma.

IgM myeloma: A multicenter retrospective study of 134 patients.

IgM myeloma is a rare hematologic malignancy for which the clinicopathological features and patient outcomes have not been extensively studied. We carried out a multicenter retrospective study in patients with diagnosis of IgM myeloma defined by >10% marrow involvement by monoclonal plasma cells, presence of an IgM monoclonal paraproteinemia of any size, and anemia, renal dysfunction, hypercalcemia, lytic lesions and/or t(11;14) identified by FISH. A total of 134 patients from 20 centers were included in this analysis. The median age at diagnosis was 65.5 years with a male predominance (68%). Anemia, renal dysfunction, elevated calcium and skeletal lytic lesions were found in 37, 43, 19, and 70%, respectively. The median serum IgM level was 2,895 mg dL-1 with 19% of patients presenting with levels >6,000 mg dL-1 . International Staging System (ISS) stages 1, 2, and 3 were seen in 40 (33%), 54 (44%), and 29 (24%) of patients, respectively. The malignant cells expressed CD20 (58%) and cyclin D1 (67%), and t(11;14) was the most common cytogenetic finding (39%). The median overall survival (OS) was 61 months. Higher ISS score was associated with worse survival (P = 0.02). Patients with IgM myeloma present with similar characteristics and outcomes as patients with more common myeloma subtypes.

[Diagnostic difficulties in amebic liver abscess].

Amebiasis is a widespread parasitic infection caused by the human-specific protozoan Entamoeba histolytica (E.- histolytica). Tropical and subtropical regions with poor socioeconomic and sanitary conditions belong to endemic areas. The highest rates of E. histolytica infection are observed in India, Mexico, Africa, some parts ofCentral and South America. Up to 90% of infections remain asymptomatic, about 10% of patients develop amebic colitis. About 10% of symptomatic individuals may present with an extraintestinal manifestation, mostly amebic liver abscess (ALA). Clinical symptoms of ALA appear within 5 months after an exposition to E. histolytica cysts. Anamnesis revealing a travel to endemic area plays a crucial role in a diagnostic process, which is further supported by an physical examination, radiological findings, serology and parasitology test. The following article presents the difficulties which may occur when the ALA is suspected in a patient traveling from endemic areas.

Central nervous system involvement by multiple myeloma: A multi-institutional retrospective study of 172 patients in daily clinical practice.

The multicenter retrospective study conducted in 38 centers from 20 countries including 172 adult patients with CNS MM aimed to describe the clinical and pathological characteristics and outcomes of patients with multiple myeloma (MM) involving the central nervous system (CNS). Univariate and multivariate analyses were performed to identify prognostic factors for survival. The median time from MM diagnosis to CNS MM diagnosis was 3 years. Thirty-eight patients (22%) were diagnosed with CNS involvement at the time of initial MM diagnosis and 134 (78%) at relapse/progression. Upon diagnosis of CNS MM, 97% patients received initial therapy for CNS disease, of which 76% received systemic therapy, 36% radiotherapy and 32% intrathecal therapy. After a median follow-up of 3.5 years, the median overall survival (OS) from the onset of CNS involvement for the entire group was 7 months. Untreated and treated patients had median OS of 2 and 8 months, respectively (P < 0.001). At least one previous line of therapy for MM before the diagnosis of CNS disease and >1 cytogenetic abnormality detected by FISH were independently associated with worse OS. The median OS for patients with 0, 1 and 2 of these risk factors were 25 months, 5.5 months and 2 months, respectively (P < 0.001). Neurological manifestations, not considered chemotherapy-related, observed at any time after initial diagnosis of MM should raise a suspicion of CNS involvement. Although prognosis is generally poor, the survival of previously untreated patients and patients with favorable cytogenetic profile might be prolonged due to systemic treatment and/or radiotherapy. Am. J. Hematol. 91:575-580, 2016. © 2016 Wiley Periodicals, Inc.

n-3 and n-6 Fatty Acid Changes in the Erythrocyte Membranes of Patients with 658240251 Clostridium difficile Infection.

The implications of circulating essential fatty acids (FA) on the inflammatory risk profile and clinical outcome are still unclear. In order to gain a deeper understanding of the role of polyunsaturated fatty acids (PUFA) in the pathogenesis of acute infection, we analyzed the FA content in red blood cell (RBC) membranes of patients with Clostridium difficile infection (CDI) and controls. We prospectively studied 60 patients including 30 patients with CDI and 30 controls to assess lipid concentrations in erythrocyte membranes using gas chromatography. We observed a higher level of saturated fatty acids (SFA) in RBC membranes from patients with CDI. In patients with CDI, we also noticed a higher level of 20:4 n-6 FA and only a small amounts of C20:2n-6, C20:3n-6 FAs, arachidonic acid (AA) precursors, which suggest an intense inflammatory reaction in the organism during infection. We also noticed low levels of n-3 FA in the RBC membranes of patients infected with CDI. There is a deficit of n-3 FA in patients with CDI. n-3 FA are probably used during CDI as precursors of pro-resolving mediators that may indicate a therapeutic role of n-3 PUFAs in CDI. The changes in fatty acids in erythrocyte membranes during CDI alter their functions which may have an impact on the clinical outcome.

The ring-stage of Plasmodium falciparum observed in RBCs of hospitalized malaria patients.

Raman spectra of the blood samples obtained directly from hospitalized malaria patients with Plasmodium falciparum (P. falciparum) in the ring-stage were analyzed. Changes observed in the Raman band intensities of the infected patients compared to healthy volunteers are the result of parasite activity inside red blood cells. The obtained spectra were discussed by analyzing differences in particular spectral regions by evaluating changes in the band intensity ratios as well as using PCA analysis. The alterations of erythrocyte membranes caused by parasite penetration are visible by a reduced I1130/I1075 intensity ratio expressing the lowering of the amount of domains arranged in trans conformation. The I2930/I2850 ratio, which is a measure of modifications in structures of membrane proteins and lipids, in infected red blood cells increases, which is caused by malaria protein export to the erythrocyte membrane and expresses the membrane disarrangement. In the pyrrole ring vibration region, the ν4 band marker of the oxygenated-Hb shows at 1371 cm(-1) whereas the ν4 band at 1353 cm(-1) related to the deoxygenated-Hb is observed for malaria patients and is characterized by a higher intensity in infected erythrocytes. The amide I analysis shows the modifications in the secondary structure composition in the infected RBCs. We found that the P. falciparum infection leads to a decrease in the α-helical content and a concurrent increase in undefined (random-coil) structures. It was observed that the Raman spectra changes are also the result of the hemozoin formation process. In the pyrrole ring stretching vibration region, the increase of 1220 cm(-1) (deoxyHb) as against 1248 cm(-1) (oxyHb) may be considered as a signal of hemozoin formation in the RBCs. Relatively intense band patterns at 1560 cm(-1) and also at 1570 cm(-1) and 1552 cm(-1) may be due to the hemozoin that is formed according to parasite activity. The results of medical diagnostic tests had not presented changes in patient RBC parameters. A significant reduction in WBC count was noticed along with a decrease in neutrophil and platelet count when compared with the control group. Although no change is observed in the overall picture of the erythrocytes, pathological changes are evident in the Raman spectrum.

Rheological properties of erythrocytes in patients infected with Clostridium difficile.

INTRODUCTION: Clostridium difficile infection (CDI) is a bacterial infection of the digestive tract. Acute infections are accompanied by increased risk for venous thromboembolism (VTE). To date, there have been no studies of the rheological properties of blood during the course of digestive tract infections. The aim of our study was to examine the effects of CDI on red blood cell (RBC) rheology, specifically RBC deformability, RBC aggregation, and plasma viscosity. In addition, the activity of glucose 6 phosphate dehydrogenase (G6PD) and acetylcholinesterase (AChE) in RBC was studied. MATERIALS AND METHODS: Our study group included 20 patients with CDI, 20 healthy persons comprised the control group. We examined the effects of CDI on the rheology of RBCs, their deformability and aggregation, using a Laser-assisted Optical Rotational Cell Analyzer (LORCA). Plasma viscosity was determined using a capillary tube plasma viscosymeter. Moreover, we estimated the activity of AChE and G6PD in RBC using spectrophotometric method. RESULTS: A statistically significant increase was found in the aggregation index, viscosity and activity of G6PD whereas the amount of time to reach half of maximum aggregation (t½) and the amplitude of aggregation (AMP) both showed statistically significantly decreases among patients with CDI compared to the control group. We also observed that the Elongation Index (EI) was decreased when shear stress values were low, between 0.3 Pa and 0.58 Pa, whereas EI was increased for shear stress in the range of 1.13-59.97 Pa. These observations were statistically significant. CONCLUSIONS: We report for the first time that acute infection of the gastrointestinal tract with Clostridium difficile is associated with abnormalities in rheological properties of blood, increased serum viscosity as well as increased aggregation of RBCs, which correlated with severity of inflammation. These abnormalities may be an additional mechanism causing increased incidence of VTE in CDI.