Non-endemic Areas Research Articles

Medical imaging in melioidosis - 20-year experience in a non-endemic Australian city.

Melioidosis may occasionally be encountered in non-endemic areas and medical imaging is frequently used to identify and characterise sites of disease. The purpose of this study is to describe the spectrum of imaging findings encountered in melioidosis patients treated in the tertiary public hospitals of Perth, Western Australia, between 2002 and 2022. A database search and electronic medical record review was used to identify cases. Cases were included if they had Burkholderia pseudomallei isolated on culture and if they had at least one diagnostic imaging study performed at a Perth public tertiary hospital. The relevant imaging studies were reviewed, and imaging findings were recorded. Thirty-six cases were identified. The most common disease manifestation was bacteraemia (72%, 26 cases), followed by pulmonary infection (58%, 21 cases), skin and soft tissue infection (22%, eight cases), prostate abscess (14%, five cases) and septic arthritis (6%, two cases). A previously unreported case of isolated melioid pleural effusion was identified, as was a case of reactivated chronic latent pulmonary melioidosis with an apparent delay of over 20 years between the onset of symptoms and the time of infection. In cases with pulmonary melioidosis, the major lung abnormalities on CT chest could be categorised into one of two distinct patterns: nodular-predominant (78%) or consolidation-predominant (22%). Further research is required to assess the utility of the pattern-based categorisation of lung abnormalities on CT chest seen in the pulmonary melioidosis cases of this series.

Rapid diagnosis of alveolar echinococcosis from lung puncture sample using metagenomic next-generation sequencing: a case report

IntroductionAlveolar echinococcosis (AE), caused by the larval forms of Echinococcus multilocularis, is a zoonotic disease affecting the liver, lungs, lymph nodes, kidneys, brain, bones, thyroid, and other organs. Diagnosing AE in a non-endemic area is usually challenging. With the rapid development and increasing application of sequencing techniques in recent years, metagenomic next-generation sequencing (mNGS) has become a powerful tool for diagnosing rare infectious diseases.Case PresentationA 45-year-old woman was admitted to the hospital for the presence of pulmonary shadows for more than 3 months. The lung computed tomography (CT) at a local hospital revealed scattered solid and quasi-circular nodules in the left upper lobe, left lower lobe, right middle lobe, and right lower lobe. The largest nodule was located in the dorsal part of the right lung, measuring 2.0 × 1.7 × 1.5 cm. Moreover, abdominal CT revealed one space-occupying lesion each in the left and right lobes. The pathological analysis of the lung biopsy specimen revealed infiltration of lymphocytes, plasma cells, and eosinophils in the alveolar wall and interstitial area. No pathogenic bacteria were observed in the sputum smear and culture tests. There were no parasite eggs in the stool. The mNGS of the lung puncture tissue revealed 6156 sequence reads matching E. multilocularis; thus, the condition was diagnosed as AE. Albendazole 400 mg was administered twice daily, and the patient was stable during follow-up.ConclusionThis case emphasizes the role of mNGS in diagnosing AE. As a novel, sensitive, and accurate diagnostic method, mNGS could be an attractive approach for facilitating early diagnosis and prompt treatment of infectious diseases, especially when the infection was caused by rare pathogens.

Ultrasound features of cutaneous myiasis: a rare case in a child.

Cutaneous myiasis is an infestation of the skin with larvae of some dipteran species. Among humans, Dermatobia hominis is the most frequently encountered dipteran responsible for cutaneous myiasis. This insect is endemic to tropical and subtropical regions, consequently, individuals travelling from non-endemic areas are most susceptible to infection due to a lack of prior exposure. Three clinical variants of myiasis are distinguished: furuncular, migratory, and wound myiasis. Furuncular myiasis represents the most common form among travelers, yet it is a rare cause of pediatric skin manifestations in developed countries. Limited awareness of this condition in non-endemic regions contributes to diagnostic challenges. In this scenario, ultrasound is useful in the diagnostic workup, enabling the identification of the viable larva.

Epidemiological characteristics of visceral leishmaniasis in Gansu Province from 2017 to 2023

To analyze the epidemiological characteristics of visceral leishmaniasis in Gansu Province from 2017 to 2023, so as to provide insights into formulation of the visceral leishmaniasis control strategy in the province. All epidemiological features of confirmed and clinically diagnosed cases of visceral leishmaniasis reported in Gansu Province from January 1, 2017 to December 31, 2023 were retrieved from the Chinese Disease Prevention and Control Information System, and the epidemiological characteristics of visceral leishmaniasis cases were analyzed descriptively. A total of 280 visceral leishmaniasis cases were reported in 39 counties (cities and districts) of Gansu Province from 2017 to 2023, including 258 local cases reported in 21 endemic counties (districts) and 22 imported cases reported in 18 non-endemic areas. Of the 280 cases, there were 262 cases with mountain type zoonotic visceral leishmaniasis (MT-ZVL), 12 cases with desert-type zoonotic visceral leishmaniasis (DT-ZVL), and 6 cases with unknown type. Re-emerging MT-ZVL occurred in Maiji District, Qinzhou District, Lixian County, Kangxian County, Zhenyuan County, Qin'an County and Yongjing County, and re-emerging DT-ZVL occurred in Dunhuang City, while emerging DT-ZVL occurred in Yumen City. The five counties (districts) reporting the highest number of visceral leishmaniasis cases included Wudu District, Wenxian County, Tanchang County, Zhouqu County and Diebu County, and a total of 220 cases were reported in these five counties, accounting for 78.57% of all visceral leishmaniasis cases in the province. Visceral leishmaniasis cases were reported each month throughout the year, with the peak in July. All reported visceral leishmaniasis cases had ages of 6 months to 81 years, including 50.71% (142/280) under 15 years of age, 49.29% (138/280) at ages of 15 years and older, and of all cases under 15 years of age, children at ages of 0 to 3 years were the most commonly affected (27.14%, 76/280). Among 280 visceral leishmaniasis cases, there were 173 males and 107 females with a male to female ratio of 1.62∶1, and farmer was the most common occupation (40.36%), followed by diaspora children (37.86%). The prevalence of visceral leishmaniasis appeared an overall tendency towards a decline in Gansu Province from 2017 to 2023; however, there are still multiple challenges for visceral leishmaniasis control in the province. Reinforced dog monitoring and management, intensified human health education and improved capability building among professionals are recommended to manage the rebounding and spread of visceral leishmaniasis.

Is yearly interferon gamma release assay latent tuberculosis infection screening warranted among patients with rheumatological diseases on disease-modifying drugs in non-endemic settings?

Patients living with rheumatologic diseases on disease-modifying antirheumatic drugs (DMARD) are at an increased risk of developing tuberculosis (TB). Current guidelines recommend screening for latent tuberculosis infection (LTBI) before initiating DMARD. However, data is lacking on the value of yearly screening for LTBI. A retrospective chart review was conducted on adult patients (≥ 18 years) with rheumatologic disease on DMARD followed longitudinally in the outpatient rheumatology clinics between 2017-2021. Collected data included patient demographics, rheumatologic diagnosis, medications, TB-related risk factors, interferon gamma release assay (IGRA) results, LTBI diagnosis and treatment. Descriptive statistics were performed. Among 339 patients, 81 (23.9%) were male, 259 (76.4%) were white, and 93 (27.5%) were Latinx. Inflammatory arthritis (84.1%) was the most common rheumatic diagnosis. Common DMARD were JAK inhibitors (19.2%), TNF-alpha inhibitors (18.9%), and IL-17 A inhibitors (18.0%). Only 2 patients at baseline had positive IGRA, and both had a history of treated LTBI. Positive IGRA tests were recorded in 1 (0.7%), 3 (1.8%), 3 (1.3%), and 3 (1.1%) in the years 2018, 2019, 2020, and 2021, respectively. Four patients converted from negative to positive during serial yearly IGRA testing. After reviewing the IGRA test and TB risk factors, only one patient was considered newly diagnosed with LTBI, requiring 4 months of rifampin. In a non-endemic area, serial IGRA testing of low-risk patients on DMARD yielded very low rate of newly diagnosed LTBI. A targeted LTBI screening based on TB-related risk factors should be performed prior to IGRA testing rather than universal yearly screening in a non-endemic setting.

Nonendemic rhinoscleroma: An unusual manifestation of the trachea.

Rhinoscleroma is classically described as a chronic granulomatous disease caused by Klebsiella rhinoscleromatis which primarily affects the nose and nasopharynx. When present, tracheal manifestations will be seen late in the disease course rather than on initial presentation. We describe a rare case of nonendemic rhinoscleroma that presented with tracheal lesions as an initial manifestation of disease. Case report and literature review. An 88-year-old male presented with longstanding dysphonia. Flexible laryngoscopy demonstrated a septal perforation and diffuse glottic lesions. CT neck demonstrated a nonobstructive polypoid tracheal lesion and mucosal thickening of the paranasal sinuses. Biopsy confirmed an atypical lympho-histiocytic proliferation and microorganisms within macrophages on Grocott methenamine silver and Steiner stains consistent with rhinoscleroma. He was referred for rheumatology and pulmonology consultation. Systemic diseases rarely affect the trachea, and even less frequently is a tracheal lesion identified as the initial manifestation of disease. The most common systemic diseases that affect the trachea include relapsing polychondritis, granulomatosis with polyangiitis, amyloidosis, and inflammatory bowel disease. The literature surrounding nasolaryngotracheal rhinoscleroma is limited, especially in nonendemic areas. It is necessary to include unusual etiologies of airway lesions in the differential diagnosis, which warrants comprehensive airway evaluation including biopsy. 4.

Not all severe malaria cases are severe: Is it time to redefine severity criteria for malaria in non-endemic regions?

BackgroundThe current definition of severe malaria in non-endemic areas follows WHO criteria, which mainly target children in malaria-endemic areas, potentially misclassifying cases in non-endemic regions. We assessed the performance of a modified severe malaria classification criteria within our patient cohort. MethodsA cohort study of patients managed for malaria in a non-endemic setting (2005–2023) was analyzed. We classified patients into severe malaria (SM) using WHO 2013 criteria except for hyperparasitemia, where 2 % threshold was applied. Patients with SM were distinguished as very severe malaria (VSM) when presenting at least one of the following conditions: parasitemia >10 %, pulmonary edema, impaired consciousness, seizures, renal failure, metabolic acidosis or hyperlactatemia, shock or hypoglycemia. In patients with SM and no criteria for VSM, less severe malaria (LSM) was defined by: 2–10 % parasitemia, hyperbilirubinemia, prostration, anemia or minor bleeding. The primary composite outcome was death or the need for a life-saving intervention, as analyzed in the three comparative groups. Secondary outcome was the prevalence of co-infections. ResultsAmong 506 patients with malaria, 176 (34.8 %) presented with SM. A total of 37 (7.3 %) patients developed a life-threatening condition, namely death (n = 4) and/or the need for life-saving interventions (n = 34). All fatalities and 33 out of the 34 life-saving interventions occurred in the VSM group. Patients in LSM group did not develop any life-threatening conditions. As to co-infections, 28 (5.5 %) patients had a community-acquired co-infection, with no differences between groups (p = 0.763). ConclusionsSeverity criteria definitions would benefit from a review when assessing patients with malaria in non-endemic areas. Within the spectrum of SM, patients reclassified as LSM have a low risk of developing a life-threatening condition and present low co-infection incidence and could benefit from management out of intensive care units and a restrictive use of empirical antibiotics.

First Evidence of Leishmania infantum Antibodies in Sheep (Ovis aries) from Southern Germany.

In Europe, Leishmania infantum is the most prevalent Leishmania species, and this protozoan is transmitted by phlebotomine sandflies. A recent publication has shown that sheep harbor L. infantum antibodies. This raises questions about the epidemiological role of small ruminants. Therefore, sera from small ruminants located in two southern German federal states, Baden-Wuerttemberg (BW) and Bavaria (BAV), were analyzed with an ELISA to determine the presence of L. infantum antibodies. The species, sex and age (gimmer vs. ewe) were recorded, and a univariate analysis was conducted to determine possible associations. In total, seven sheep flocks (274 sheep/10 goats) from BW and seven sheep flocks (277 sheep/78 goats) from BAV were examined. In BW, four sheep from three flocks tested positive for L. infantum antibodies. In BAV, the same number of positive sheep were detected but in four flocks. The total seropositivity rate in sheep was 1.45%. All goats tested negative. No significant association (p > 0.05) was detected between Leishmania seropositivity and the variables evaluated. Our study reveals the exposure of sheep to L. infantum in a non-endemic area. Further investigation is needed to determine whether sheep can be used as sentinels to identify new phlebotomine habitats and Leishmania risk areas.

Enhancing Diagnosis and Treatment Adjustments for Travelers Infected with Burkholderia pseudomallei: A Case Report - Beijing Municipality, China, June 2023.

Burkholderia pseudomallei (BP) infection leads to melioidosis, a tropical disease endemic to coastal provinces of southern China. Physicians in non-endemic areas, do not commonly consider this disease as a primary differential diagnosis for febrile patients. This article discusses a case of melioidosis in Northern China. The patient, who had recently visited a Southeast Asian region with high melioidosis prevalence, fell ill after exposure to contaminated water. The disease progressed quickly and with severity. Healthcare workers need to remain vigilant regarding travel-related diseases for accurate differential diagnosis and to provide timely and effective treatment, especially for patients with recent travel history or symptoms during travel.

Combustion-Derived Pollutants Linked with Kidney Disease in Low-Lying Flood-Affected Areas in the Balkans.

Tens of thousands of people in southern Europe suffer from Balkan endemic nephropathy (BEN), and four times as many are at risk. Incidental ingestion of aristolochic acids (AAs), stemming from the ubiquitousAristolochia clematitis(birthwort) weed in the region, leads to DNA adduct-induced toxicity in kidney cells, the primary cause of BEN. Numerous cofactors, including toxic organics and metals, have been investigated, but all have shown small contributions to the overall BEN relative to non-BEN village distribution gradients. Here, we reveal that combustion-derived pollutants from wood and coal burning in Serbia also contaminate arable soil and test as plausible causative factors of BEN. Using a GC-MS screening method, biomass-burning-derived furfural and coal-burning-derived medium-chain alkanes were detected in soil samples from BEN endemic areas levels at up to 63-times and 14-times higher, respectively, than in nonendemic areas. Significantly higher amounts were also detected in colocated wheat grains. Coexposure studies with cultured kidney cells showed that these pollutants enhance DNA adduct formation by AA, - the cause of AA nephrotoxicity and carcinogenicity. With the coincidence of birthwort-derived AAs and the widespread practice of biomass and coal burning for household cooking and heating purposes and agricultural burning in rural low-lying flood-affected areas in the Balkans, these results implicate combustion-derived pollutants in promoting the development of BEN.

Concurrent Extraparenchymal and Spinal Neurocysticercosis in an Immunocompetent Patient Treated for Obstructive Hydrocephalus and Spinal Cord Compression

Introduction: Neurocysticercosis (NCC) is a condition caused by infection of the central nervous system (CNS) by Taenia solium, or pork tapeworm, larvae. Despite commonly infecting the CNS, it may be easily misdiagnosed for more common pathologies, such as arachnoid cysts or tumors. Though most frequently seen in endemic areas, immigration patterns are altering its traditional distribution. Extraparenchymal neurocysticercosis (including ventricular, spinal, and subarachnoid types) carries a poorer prognosis Objective: We present a case of NCC presenting in a young immunocompetent patient which was initially thought to be an arachnoid cyst due to non-pathognomonic imaging results and symptoms. This case illustrates a challenging NCC diagnosis. Case Report: A 24-year-old male without known past medical history presented with 2 years of chronic headache, 2 months of blurry vision in the left eye, and 1 week of progressive nausea and vomiting found to have aqueductal stenosis with obstructive hydrocephalus and bilateral 1.5 cm, peripherally-enhancing cystic lesions of the cerebellopontine angle with associated mass effect, initially described as arachnoid cysts, as well as a left sided foramen magnum cyst. He had an external ventricular drain placed and later underwent ventriculoperitoneal shunt (VPS) insertion. He presented 10 days later with sepsis symptoms and the initial workup was concerning for tuberculosis-associated meningitis and he underwent shunt externalization and re-internalization after clinical improvement, though he was lost to follow up. Two months later he presented with acute urinary retention and right sided weakness. He had spinal cord compression of the cervicothoracic and thoracolumbar spine due to cystic lesion and underwent right C7-T1 and T10-T11 hemilaminotomies for cyst resection, with pathology consistent with NCC. Conclusion: Neurocysticercosis (NCC) is a complex disease which is largely overlooked and is increasing in prevalence in non-endemic areas such as the United States. NCC has various symptoms and presentations depending on location and progression of larval development, which may mimic more common pathologies. The clinical manifestations depend on the parasite load and the host’s immune response regarding their location in CNS and their evolutionary stage. There are two types of NCC, the parenchymal and the extraparenchymal form. The extraparenchymal racemose NCC has the worst prognosis among all forms of NCC with mortality ranging between 30% and 80%. This reinforces the need for a broad differential diagnosis in these scenarios, as well as the importance of close Infectious Disease follow up for patients diagnosed with concurrent cranial and spinal NCC.

Prospective evaluation of the relevance of Epstein-Barr virus antibodies for early detection of nasopharyngeal carcinoma in Chinese adults.

Epstein-Barr virus (EBV) is a major cause of nasopharyngeal carcinoma (NPC) and measurement of different EBV antibodies in blood may improve early detection of NPC. Prospective studies can help assess the roles of different EBV antibodies in predicting NPC risk over time. A case-cohort study within the prospective China Kadoorie Biobank of 512 715 adults from 10 (including two NPC endemic) areas included 295 incident NPC cases and 745 subcohort participants. A multiplex serology assay was used to quantify IgA and IgG antibodies against 16 EBV antigens in stored baseline plasma samples. Cox regression was used to estimate adjusted hazard ratios (HRs) for NPC and C-statistics to assess the discriminatory ability of EBV-markers, including two previously identified EBV-marker combinations, for predicting NPC. Sero-positivity for 15 out of 16 EBV-markers was significantly associated with higher NPC risk. Both IgA and IgG antibodies against the same three EBV-markers showed the most extreme HRs, i.e. BGLF2 (IgA: 124.2 (95% CI: 63.3-243.9); IgG: 8.6 (5.5-13.5); LF2: [67.8 (30.0-153.1), 10.9 (7.2-16.4)]); and BFRF1: 26.1 (10.1-67.5), 6.1 (2.7-13.6). Use of a two-marker (i.e. LF2/BGLF2 IgG) and a four-marker (i.e. LF2/BGLF2 IgG and LF2/EA-D IgA) combinations yielded C-statistics of 0.85 and 0.84, respectively, which persisted for at least 5 years after sample collection in both endemic and non-endemic areas. In Chinese adults, plasma EBV markers strongly predict NPC occurrence many years before clinical diagnosis. LF2 and BGLF2 IgG could identify NPC high-risk individuals to improve NPC early detection in community and clinical settings.

ELISA with recombinant antigen Lb6H validated for the diagnosis of American tegumentary leishmaniasis.

American tegumentary leishmaniasis (ATL) diagnosis is an open question, and the search for a solution is urgent. The available tests that detect the etiological agent of the infection are specific for ATL diagnosis. However, they present disadvantages, such as low sensitivity and the need for invasive procedures to obtain the samples. Immunological methods (leishmanin skin test and search for anti-Leishmania antibodies) are good alternatives to the etiological diagnosis of ATL. Presently, we face problems with disease confirmation due to the discontinuity in the production of leishmanin skin test antigen, particularly in resource-poor settings. Aiming to diagnose ATL, we validated rLb6H-ELISA for IgG antibodies using 1,091 samples from leishmaniasis patients and healthy controls, divided into four panels, living in 19 Brazilian endemic and non-endemic states. The rLb6H-ELISA showed a sensitivity of 98.6% and a specificity of 100.0%, with the reference panel comprising 70 ATL patient samples and 70 healthy controls. The reproducibility evaluation showed a coefficient of variation of positive samples ≤ 8.20% for repeatability, ≤ 17,97% for reproducibility, and ≤ 8.12% for homogeneity. The plates sensitized with rLb6H were stable at 4°C and -20°C for 180 days and 37°C for seven days, indicating 12 months of validity. In samples of ATL patients from five research and healthcare centers in endemic and non-endemic areas, rLb6H-ELISA showed a sensitivity of 84.0%; no significant statistical difference was observed among the five centers (chi-square test, p = 0.13). In samples of healthy controls from four areas with different endemicity, a specificity of 92.4% was obtained; lower specificity was obtained in a visceral leishmaniasis high endemicity locality (chi-square test, p<0.001). Cross-reactivity was assessed in 166 other disease samples with a positivity of 13.9%. Based on the good diagnostic performance and the reproducibility and stability of the antigen, we suggest using ELISA-rLb6H to diagnose ATL.

First detection of feline sporotrichosis (Sporothrix brasiliensis) at the zoonoses control service in Campo Grande, Mato Grosso do sul, Brazil.

Sporotrichosis is a traumatic mycosis affecting the skin or subcutaneous tissues caused by Sporothrix dimorphic fungus. The fungal complex includes several pathogenic species, out of which S. brasiliensis and S. schenckii are predominant in Brazil. In Mato Grosso do Sul (MS) state, the first human and animal cases were reported in 2016 in Corumbá and Ladário cities. Accordingly, we present the first occurrences of feline sporotrichosis detected in the state capital Campo Grande, MS, by the Zoonoses Control Service (ZCS) of the Municipal Public Health Department. The study included four allochthonous cases of feline sporotrichosis originating from Corumbá, MS, attended by the ZCS. All four cats presented classical clinical signs of sporotrichosis, as ulcerative nodular cutaneous lesions. Three slides tested positive by direct microscopy and PCR, followed by Sanger sequencing confirmed Sporothrix brasiliensis in two samples. The initial suspicion and diagnosis of feline sporotrichosis at the ZCS highlights the importance of accurate surveillance of sporotrichosis in non-endemic areas to enhance the capacity to prevent, detect and respond to emerging diseases in Campo Grande.

Clinical features of ocular tuberculosis

Ocular tuberculosis, a severe pathology of the eye, involves problems of diagnosis and treatment. The clinical manifestations presented in the specialized literature are very varied and differ in endemic areas for tuberculosis and non-endemic areas. For the effectiveness of the management of ocular tuberculosis, it is important to know the clinical peculiarities specific to the geographical area and to maintain vigilance for this serious pathology.

Des-gamma-carboxy prothrombin (DCP) as a prognostic biomarker in patients with advanced hepatocellular carcinoma treated with atezolizumab/bevacizumab.

e16167 Background: Causes of variable disease response to first-line treatment with atezolizumab plus bevacizumab in patients with advanced hepatocellular carcinoma (HCC) remain unclear. Identifying tumor markers that predict treatment response and provide prognostic information may help clinicians optimize treatment strategies and patient outcomes. The role of des-gamma-carboxy prothrombin (DCP) is not well established in Hepatitis B Virus non-endemic areas. This study aimed to investigate DCP as a predictive biomarker of treatment response as well as explore prognostic implications of DCP in patients with advanced HCC. Methods: This single-center retrospective analysis evaluated DCP and radiographic response in patients with advanced HCC who received atezolizumab/bevacizumab in the first-line setting. DCP was measured at the time of best response, determined by radiographic evaluation, and compared to day one of atezolizumab/bevacizumab initiation. Elevated DCP was defined as &gt; = 7.5 ng/mL. DCP response was defined as a decrease of &gt; = 50% at response assessment compared with baseline. Comparisons of treatment effects were performed using two-tailed Fisher Exact Probability Test. Overall survival (OS) was defined as the interval between the first treatment and either the date of death or the last follow-up visit. OS was analyzed using the Kaplan–Meier method and compared between groups using the log-rank test. Results: A total of 53 patients with advanced HCC treated with atezolizumab/bevacizumab were included. Radiographic treatment responses were complete response 3.8%, partial response 22.6%, stable disease 52.8% and progression of disease 20.8%, respectively. On day one of treatment 70% of patients had an elevated DCP. Patients with DCP response had ORR of 69% (odds ratio, 15.75; 95% CI, 3.50 – 70.9; p = 0.0002) and disease control rate of 100% (p = 0.047). Conversely, patients with &gt; = 50% increase in DCP at response evaluation compared to day one of treatment had ORR of 4.5% and no response rate of 95% (p = 0.0035). Furthermore, patients who had &gt; = 50% increase in DCP had median OS of 15.4 months compared to patients without &gt; = 50% increase in DCP who had median OS of 28.4 months (HR = 2.48; 95% CI, 1.035 – 5.93; p = 0.042). There was no difference in ORR, or OS, between patients who had elevated DCP on day one of treatment and those who did not. Conclusions: DCP response correlates with objective radiographic response in patients with advanced HCC treated with atezolizumab plus bevacizumab in the first-line setting. DCP increase of &gt; = 50% correlates with decreased median OS and may serve as a negative prognostic biomarker in such patients.

Rickettsia africae infections in sub-Saharan Africa: A systematic literature review of epidemiological studies and summary of case reports.

Rickettsia africae is a tick-borne bacteria known to cause African tick bite fever (ATBF). While the disease was first described more than 100 years ago, knowledge of transmission risk factors and disease burden remain poorly described. To better understand the burden of R. africae, this article reviewed and summarized the published literature related to ATBF epidemiology and clinical management. Using a systematic approach, consistent with the PRISMA guidelines, we identified more than 100 eligible articles, including 65 epidemiological studies and 41 case reports. Most reports described R. africae in ticks and livestock, while human studies were less common. Human disease case reports were exclusively among returning travellers from non-endemic areas, which limits our disease knowledge among at-risk populations: people living in endemic regions. Substantial efforts to elucidate the ATBF risk factors and clinical manifestations among local populations are needed to develop effective preventative strategies and facilitate appropriate and timely diagnosis.

Lab on a chip (LOC) platform for drug screening against the intracellular forms of Trypanosoma cruzi

Trypanosoma cruzi is the etiological agent of Chagas disease, endemic in Latin America with recent spreading to non-endemic areas due to human migration. The low efficacy and substantial prevalence of side effects of the approved medications benznidazole (BZN) and nifurtimox observed mainly during the chronic phase of Chagas disease, when most patients receive their diagnosis, demonstrate the need to find new therapeutic compounds to address this neglected global health disease. Here, we developed a platform for screening the antitrypanosomal activity of compounds over intracellular amastigotes using microfluidics, LOC devices, and advanced image analysis algorithms. This platform allows the simultaneous testing of six different concentrations of a compound and the automatic and high-precision processing of the images obtained during the experimental phase, providing quickly and easily a multitude of statistical data for the screening of new drugs. To assess the developed platform, we analyzed the effects of BZN as a reference drug and compared the dose–response curves with those obtained with a flow cytometry-based method, obtaining similar IC50 results. Furthermore, a collection of compounds obtained by chemical synthesis from a combinatorial library was tested over intracellular amastigotes in infected Vero cells.

#2373 Malignant tumors of the urinary bladder and Balkan endemic nephropathy – a 45 year study

Abstract Background and Aims Balkan endemic nephropathy (BEN) is a chronic interstitial kidney disease limited geographically to specific regions. The wider importance of BEN is reflected in its associations with malignant tumors of the urothelium. For researchers, malignant tumors of the urinary bladder (MTUB) have been less studied and perhaps considered less interesting compared to malignant tumors of the upper urothelium. Balkan endemic nephropathy (BEN) is a chronic interstitial kidney disease limited geographically to specific regions. The wider importance of BEN is reflected in its associations with malignant tumors of the urothelium. For researchers, malignant tumors of the urinary bladder (MTUB) have been less studied and perhaps considered less interesting compared to malignant tumors of the upper urothelium. Method Balkan endemic nephropathy (BEN) is a chronic interstitial kidney disease limited geographically to specific regions. The wider importance of BEN is reflected in its associations with malignant tumors of the urothelium. For researchers, malignant tumors of the urinary bladder (MTUB) have been less studied and perhaps considered less interesting compared to malignant tumors of the upper urothelium. Results During the observed period, there were a total of 1447 cases of MTUB - 1109 (76.64%) male patients and 338 (33.36%) female patients. The average annual incidence rate (AAIR) of MTUB in endemic settlements for the observed period (1978-2024) is 15.64; in hypoendemic areas is 13.89, and in non-endemic areas is 14.62. The AAIR of MTUB in endemic settlements is 1.13 times higher than the rate in hypoendemic areas and 1.07 times higher compared to non-endemic settlements. It is noteworthy that in the first period of observation, the AAIR of MTUB in endemic areas is 2.24 times higher than the rate in hypoendemic areas and 4.09 times higher than the rate in non-endemic areas. However, in the second and third periods of the study, it is significantly lower compared to the rates in hypoendemic and non-endemic areas. The linear trend of MTUB for the observed period in endemic settlements is negative without statistical significance (y = −0.012x + 701; r2 = 0.048), while in non-endemic areas, it is positive and statistically significant (y = 1.340x + 0.172; r2 = 0.647). Conclusion The higher frequency of MTUB in the Jablanica district over the 45-year study of the region with BEN is limited to the first part of the research and may indicate a common nephropathogenic and carcinogenic etiological factor, confirming a positive correlation between BEN and malignant urothelial tumors. At the same time, in the last 25 years of the observed period, there has been a drastic decline in the frequency of both BEN and MTUB, as well as malignant tumors of the upper urothelium.

Blastocystis hominis -associated Acute Appendicular Peritonitis in a 9-Year-old Boy: A Case Report and a Comprehensive Review of the Literature.

Although Blastocystis sp. has been classically considered a commensal parasite with limited pathogenicity, recent studies suggest that its pathogenic potential is high. We report the case of a 9-year-old Spanish male who presented with peritonitis secondary to acute appendicitis with abundant intra-abdominal turbid-free fluid. A standard appendectomy was performed, and a sample of the fluid was taken for microbiological culture. Multimicrobial flora was isolated in peritoneal fluid culture. The antibiotic resistance study showed that all the microorganisms were sensitive to meropenem. On the 5th postoperative day, a control blood test showed relative eosinophilia and a persistently elevated C-reactive protein. A stool parasitological study showed abundant cysts morphologically compatible with Blastocystis hominis . The hematoxylin & eosin and Giemsa study identified abundant parasitic cysts in the appendix. The patient evolved favorably and is currently asymptomatic and under follow-up. Regarding acute appendicitis, there is only one report in the literature of peritonitis of appendiceal origin associated with Blastocystis sp. In conclusion, although infrequent, parasitosis should be considered as a potential etiological agent of acute appendicitis, even in nonendemic areas. Relative eosinophilia or persistently elevated acute phase reactants despite adequate antibiotic coverage should help to establish diagnostic suspicion.