A Case of Rapidly Diagnosed Mycobacterium intracellulare in a Frail Geriatric Patient With Multimorbidity.

The prevalence of non-tuberculous mycobacteria (NTM) infections has been on the rise in recent years, especially among the elderly population and other immunocompromised groups. Risk factors for NTM infections include advanced age, preexisting pulmonary diseases, and low body mass index. This study presents a case of NTM pulmonary disease attributed to Mycobacterium intracellulare, which was rapidly identified using metagenomic next-generation sequencing (mNGS). An 82-year-old male presented with persistent fever, cough, and shortness of breath. Initial assessments revealed an elevated white blood cell count and high-sensitivity C-reactive protein, with chest CT showing newly formed nodular shadows and cavity formation. Sputum tests confirmed NTM infection through positive acid-fast staining and mNGS, which rapidly identified M. intracellulare within 48 hours. Subsequent sputum samples confirmed the diagnosis using traditional methods. The patient had a complex medical history, including pulmonary tuberculosis, chronic pancreatitis, chronic hepatitis B, diabetes, and malnutrition. The patient was treated with a combination of cefotaxime, moxifloxacin, clarithromycin, and acetylcysteine, in addition to receiving nutritional support. After the treatment, there was an improvement in symptoms, normalization of body temperature, and a decrease in cough and sputum production. This case highlights the significance of mNGS in promptly diagnosing and treating NTM pulmonary disease, especially in elderly patients with various underlying health conditions. The collaborative effort among different medical specialties enabled more thorough patient care, ultimately leading to better outcomes. Incorporating cutting-edge diagnostic techniques such as mNGS alongside a holistic treatment approach is crucial for the successful management of NTM infections in at-risk populations.

Clinical Impact of Plasma Metagenomic Next-Generation Sequencing on Infection Diagnosis and Antimicrobial Therapy in Immunocompromised Patients.

BACKGROUND: Clinical impact of plasma metagenomic next-generation sequencing (mNGS) on infection diagnosis and antimicrobial therapy in immunocompromised patients with suspected infection remains unclear. METHODS: Between March and December 2022, 424 cases with fever, infection history, mechanical ventilation, or imaging abnormalities underwent plasma mNGS testing at a single center. Eleven patients have received solid organ transplantation, and the remaining patients were categorised into febrile neutropenia (FN), non-neutropenia (NN), and non-haematologic disease (NTHD) groups based on immunosuppression severity. The diagnostic rate of infection and the utilisation of antimicrobial agents based on mNGS were assessed. RESULTS: The use of mNGS significantly improved the diagnostic rates for fungi in the FN (56.1%, P = 0.003) and NN (58.8%, P = 0.008) groups versus the NHD group (33.3%). Positive impacts associated with therapy were significantly greater than negative impacts across all three groups (all P < 0.001), and the utilisation of escalation therapy was significantly more frequent in the FN group than in the NN groups (P = 0.006). Over 70% of cases with negative mNGS results across the three groups underwent de-escalation therapy, with >1/3 being discontinued, preventing antimicrobial overuse. CONCLUSIONS: Plasma mNGS has a clinically confirmed positive impact in immunocompromised patients with neutropenia, improving the diagnosis of fungal infections and antimicrobial therapy.

Application of metagenomic next-generation sequencing for rapid molecular identification in spinal infection diagnosis.

Objective: This study aimed to determine the sensitivity and specificity of metagenomic next-generation sequencing (mNGS) for detecting pathogens in spinal infections and to identify the differences in the diagnostic performance between mNGS and targeted next-generation sequencing (tNGS). Methods: A total of 76 consecutive patients with suspected spinal infections who underwent mNGS, culture, and histopathological examinations were retrospectively studied. The final diagnosis of the patient was determined by combining the clinical treatment results, pathological examinations, imaging changes and laboratory indicators. The sensitivity and specificity of mNGS and culture were determined. Results: The difference between the two detection rates was statistically significant (p < 0.001), with mNGS exhibiting a significantly higher detection rate (77.6% versus 18.4%). The average diagnosis time of mNGS was significantly shorter than that of bacterial culture (p < 0.001, 1.65 versus 3.07 days). The sensitivity and accuracy of mNGS were significantly higher than that of the culture group (p < 0.001, 82.3% versus 17.5%; 75% versus 27.6%), whereas the specificity of mNGS (42.9%) was lower than that of the culture group (p > 0.05, 42.9% versus 76.9%). The sensitivity, specificity, accuracy, and positive predictive value (PPV) of pus were higher than those of tissue samples for mNGS, whereas for culture, the sensitivity, specificity, accuracy, and PPV of tissue samples were higher than those of pus. tNGS demonstrated higher sensitivity and accuracy in diagnosing tuberculosis (TB) than mNGS (80% versus 50%; 87.5% versus 68.8%). Conclusion: mNGS for spinal infection demonstrated better diagnostic value in developing an antibiotic regimen earlier, and it is recommended to prioritize pus samples for testing through mNGS. Moreover, tNGS outperformed other methods for diagnosing spinal TB and identifying antibiotic-resistance genes in drug-resistant TB.

A case report and literature review: Mycobacterium leprae infection diagnosed by metagenomic next-generation sequencing of cerebrospinal fluid.

BACKGROUND: Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) that is responsible for deformities and irreversible peripheral nerve damage and has a broad spectrum of clinical and serological manifestations. Leprosy primarily affects the peripheral nerves and rarely presents with central nervous system involvement. Diagnosing leprosy can still be difficult in some cases, especially when the infection involves uncommon clinical manifestations and extracutaneous sites. Delayed diagnosis and treatment of leprosy may lead to irreversible damage and death. CASE PRESENTATION: We report a case of a 30-year-old female presenting with "repeated high fever with symptoms of headache for 14 days". On the day of admission, physical signs of lost eyebrows and scattered red induration patches all over her body were observed. The patient's diagnosis was based on the clinical characteristics using a combination of metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) and slit-skin smear. After confirming Listeria meningitis and multibacillary leprosy with erythema nodosum leprosum (ENL), a type 2 reaction, she was treated with ampicillin sodium, dapsone, rifampicin, clofazimine, methylprednisolone, and thalidomide. At the 1-year follow-up, the frequency and severity of headaches have significantly decreased and a good clinical response with improved skin lesions was found. CONCLUSION: This case highlights the importance of considering leprosy, which is a rare and underrecognized disease, in the differential diagnosis of skin rashes with rheumatic manifestations, even in areas where the disease is not endemic, and physicians should be alerted about the possibility of central nervous system infections. In addition, mNGS can be used as a complementary diagnostic tool to traditional diagnostic methods to enhance the diagnostic accuracy of leprosy.

Disseminated Acanthamoeba castellanii infection in a patient with AIDS: a case report and literature review.

Background: Acanthamoeba castellanii infection is a rare condition primarily occurring in immunocompromised patients with extremely high mortality. Currently, there is no standard treatment for this condition, and successful treatment reports are scarce. Case presentation: We present a case of Acanthamoeba castellanii infection in a 63-year-old female patient with AIDS, who was admitted to our hospital with symptoms of fever, skin ulcers, subcutaneous nodules, and food regurgitation from the nose while eating. After initial empirical treatment failed, a biopsy of the subcutaneous nodule was performed, and metagenomic next-generation sequencing (mNGS) technology was used to detect pathogenic microorganisms in both the biopsy specimen and blood samples. The results revealed Acanthamoeba castellanii infection. Additionally, histopathological examination of the biopsy specimen and cytological examination of the secretions from the ulcer surface also confirmed this pathogenic infection. The patient's symptoms significantly improved upon discharge after adjusting the treatment regimen to a combination of anti-amebic therapy. Conclusion: Immunocompromised patients presenting with unexplained fever and skin or sinus lesions should be evaluated for Acanthamoeba castellanii infection. Multi-drug combination therapy is required for this organism infection, and a standard treatment protocol still needs further research. Metagenomic next-generation sequencing is a valuable tool for early diagnosis of unknown pathogen infections.

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

INTRODUCTION: Alveolar 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 PRESENTATION: A 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. CONCLUSION: This 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.

Torquetenovirus from bronchoalveolar lavage fluid as a biomarker for lung infection among immunocompromised hosts.

Aim: Torquetenovirus (TTV) was a promising biomarker for immunity, while lung regional TTV for evaluating the opportunistic infection among immunocompromised hosts (ICH) was unclear. Materials & methods: In the ICH and non-ICH populations, we compared the susceptibility to opportunistic infections, clinical severity and the prognosis between subgroups, respectively. Results: ICH with detectable bronchoalveolar lavage fluid (BALF)-TTV were more susceptible to lung aspergillosis and Mycobacterium infections. Furthermore, our data demonstrated that the ICH cohort with detectable BALF-TTV represented a higher clinical severity and a worse prognosis, while the above findings were not found in the non-ICH population. Conclusion: Our findings demonstrated that the BALF-TTV could act as an effective predictor for opportunistic infection for ICH that complemented the CD4+ T cell counts.

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Metagenomic Next-Generation Sequencing as an Effective Diagnostic Tool for Talaromycosis in HIV-Negative Patients.

The diagnosis of Talaromyces marneffei infection in HIV-negative patients remains challenging. There is an urgent need for rapid and convenient methods to diagnose this complicated disease. The aim of this study was to evaluate the diagnostic efficiency of metagenomic next-generation sequencing (mNGS) for talaromycosis in non-HIV-infected patients by comparing mNGS with traditional microbial culture. In total, 66 samples from 57 patients were analyzed via both mNGS and microbial culture. The ROC curve showed a sensitivity for mNGS of 97.22%, which was greater than that of microbial culture (61.11%). Samples from the respiratory tract, infectious skin lesions, and lymph nodes are recommended as routine samples for talaromycosis detection via mNGS. Furthermore, mNGS significantly reduced the diagnostic time compared to microbial culture. Overall, our study demonstrated that mNGS is a promising tool for rapid and accurate pathogenic detection in HIV-negative patients with talaromycosis.

The impact of neutrophil count on the results of metagenomic next-generation sequencing in immunocompromised febrile children.

Metagenomic next-generation sequencing (mNGS) has revolutionized the detection of pathogens, particularly in immunocompromised individuals such as pediatric patients undergoing intensive chemotherapy and hematopoietic stem cell transplantation. This study aims to explore the impact of neutrophil count on the diagnostic efficacy of mNGS in diagnosing infections in pediatric patients with febrile diseases. We conducted a retrospective analysis of pediatric patients with febrile diseases in the hematology/oncology department from January 2019 to September 2022. The study included 387 patients with 516 febrile episodes. Analyzing data from 516 pediatric cases, our study found that 70.7 % had febrile neutropenia (FN) and 29.3 % had febrile without neutropenia (FWN). mNGS demonstrated a high positive detection rate of 84.9 %, compared to 29.7 % for conventional microbiological tests (CMT). While the positive detection rates of mNGS were similar in both FN and FWN groups, bacterial pathogens were more frequently detected in FN patients. Furthermore, the rate of identifying a "probable" microbial etiology was lower in the FN group (46.8 %) compared to the FWN group (65.6 %, p＜0.001). When analyzing the types of organisms and specimens, the "probable" identification rates were particularly lower for viruses and fungi detected by mNGS, as well as in blood and nasopharyngeal swab samples. These findings underscore the significant influence of neutrophil counts on mNGS results in pediatric febrile patients and highlight the necessity for tailored diagnostic approaches in this population.

Perichondritis of the auricle: bacterial or fungal? (A case series).

BACKGROUND: Suppurative perichondritis of the auricle is a common disease that can easily cause malformations if it develops into an uncontrolled infection. In nearly half of the cases, otolaryngologists cannot identify the pathogens involved. CASE PRESENTATION: In the present work, we described two cases of pyogenic perichondritis, with negative on conventional culture. However, using metagenomic next-generation sequencing (mNGS), we detected fungal infections in the patients and after the patients were given anti-fungal treatment, the patients achieved a good prognosis. CONCLUSIONS: These cases highlighted the possibility that fungi might be the involved pathogens in patients who have had multiple negative bacterial cultures, and mNGS should be applied in these cases. mNGS could be used as a supplement to traditional culture methods.

Clinical diagnostic value of targeted next­generation sequencing for infectious diseases (Review).

As sequencing technology transitions from research to clinical settings, due to technological maturity and cost reductions, metagenomic next­generation sequencing (mNGS) is increasingly used. This shift underscores the growing need for more cost­effective and universally accessible sequencing assays to improve patient care and public health. Therefore, targeted NGS (tNGS) is gaining prominence. tNGS involves enrichment of target pathogens in patient samples based on multiplex PCR amplification or probe capture with excellent sensitivity. It is increasingly used in clinical diagnostics due to its practicality and efficiency. The present review compares the principles of different enrichment methods. The high positivity rate of tNGS in the detection of pathogens was found in respiratory samples with specific instances. tNGS maintains high sensitivity (70.8­95.0%) in samples with low pathogen loads, including blood and cerebrospinal fluid. Furthermore, tNGS is effective in detecting drug­resistant strains of Mycobacterium tuberculosis, allowing identification of resistance genes and guiding clinical treatment decisions, which is difficult to achieve with mNGS. In the present review, the application of tNGS in clinical settings and its current limitations are assessed. The continued development of tNGS has the potential to refine diagnostic accuracy and treatment efficacy and improving infectious disease management. However, further research to overcome technical challenges such as workflow time and cost is required.

Case report: Successful combination therapy with isavuconazole and amphotericin B in treatment of disseminated Candida tropicalis infection.

Disseminated candidiasis is a severe complication in patients with hematological malignancies who have undergone chemotherapy or hematopoietic stem cell transplantation. It has a high mortality rate. When disseminated candidiasis caused by Candida tropicalis involves either the brain or heart, the prognosis is extremely poor. Traditional methods such as cultures are limited in diagnosing disseminated candidiasis. We describe a case report of a 55-year-old man with acute myeloid leukemia who developed candidemia caused by Candida tropicalis after chemotherapy, which disseminated extensively to the heart, brain, skin, liver, spleen and kidneys. In this instance, the patient was rapidly diagnosed with candida infection by metagenomic next generation sequencing, and successfully treated with combination therapy of isavuconazole and amphotericin B. The patient continued with treatment of leukemia while simultaneously receiving antifungal therapy, and both leukemia and disseminated candidiasis were effectively controlled. This case report provides real-world experience for treatment of patients with leukemia complicated by disseminated candidiasis.

Comparison of plasma and blood cell samples in metagenomic next-generation sequencing for identification of the causative pathogens of fever.

Background: Metagenomic next-generation sequencing (mNGS) of plasma DNA has become an attractive diagnostic method for infectious diseases; however, the rate of false-positive results is high. This study aims to evaluate the diagnostic accuracy of mNGS in plasma versus blood cell samples for immunocompromised children with febrile diseases. Methods: The results of conventional microbiological test (CMT) and mNGS using plasma and blood cells in 106 patients with 128 episodes of febrile diseases from the Department of Hematology/Oncology were analyzed and described. Results: The positivity rates for CMT and mNGS of plasma and blood cells were 35.9 %, 84.4 % and 46.9 %, respectively (P < 0.001). Notably, mNGS identified multiple pathogens in a single specimen in 68.5 % of plasma samples and 38.3 % of blood cell samples (P < 0.001). Furthermore, plasma and blood cell mNGS identified causative pathogens in 58 and 46 cases, accounting for 53.7 % and 76.7 % of the mNGS-positive cases for each sample type, respectively (P = 0.002). By integrating results from both plasma and blood cell samples, causative pathogens were identified in 77 cases (60.2 %), enhancing sensitivity to 87.5 % but reducing specificity to 15.0 %, compared to plasma (65.9 % sensitivity and 20.0 % specificity) and blood cell samples (52.3 % sensitivity and 80.0 % specificity). Conclusions: mNGS of plasma is sensitive but has a high false-positive rate, while mNGS of blood cells has low sensitivity but higher specificity.

[Auxiliary diagnosis of visceral leishmaniasis with metagenomic next-generation sequencing: a case report].

This case report summarizes the experience from diagnosis and treatment of a patient with repeated high fever, hepatosplenomegaly and pancytopenia. Following exclusion of bacterial, viral, fungal infections and hematological diseases, metagenomic next-generation sequencing of the patient's peripheral blood revealed Leishmania infantum infection, and rK39 rapid diagnostic test showed positive for anti-Leishmania antibody, while microscopic examination of bone marrow smears identified Leishmania amastigotes. Therefore, the case was definitively diagnosed as visceral leishmaniasis, and given anti-infective treatment with sodium antimony gluconate and hormone, hepatoprotection, elevation of white blood cell counts and personalized nursing. Then, the case was cured and discharged from hospital. Metagenomic next-generation sequencing is of great value in etiological detection of fever patients with unknown causes, which deserves widespread clinical applications.

The diagnostic value of bronchoalveolar lavage fluid metagenomic next-generation sequencing in critically ill patients with respiratory tract infections.

Metagenomic next-generation sequencing (mNGS) is an unbiased and rapid method for detecting pathogens. This study enrolled 145 suspected severe pneumonia patients who were admitted to the Affiliated Hospital of Jining Medical University. This study primarily aimed to determine the diagnostic performance of mNGS and conventional microbiological tests (CMTs) using bronchoalveolar lavage fluid samples for detecting pathogens. Our findings indicated that mNGS performed significantly higher sensitivity (97.54% vs 28.68%, P < 0.001), coincidence (90.34% vs 35.17%, P < 0.001), and negative predictive value (80.00% vs 13.21%, P < 0.001) but performed lower specificity than CMTs (52.17% vs 87.5%, P < 0.001). Streptococcus pneumoniae as the most common bacterial pathogen had the largest proportion (22.90%, 30/131) in this study. In addition to bacteria, fungi, and virus, mNGS can detect a variety of atypical pathogens such as Mycobacterium tuberculosis and non-tuberculous. Mixed infections were common in patients with severe pneumonia, and bacterial-fungal-viral-atypical pathogens were the most complicated infection. After adjustments of antibiotics based on mNGS and CMTs, the clinical manifestation improved in 139 (95.86%, 139/145) patients. Our data demonstrated that mNGS had significant advantage in diagnosing respiratory tract infections, especially atypical pathogens and fungal infections. Pathogens were detected timely and comprehensively, contributing to the adjustments of antibiotic treatments timely and accurately, improving patient prognosis and decreasing mortality potentially.IMPORTANCEMetagenomic next-generation sequencing using bronchoalveolar lavage fluid can provide more comprehensive and accurate pathogens for respiratory tract infections, especially when considering the previous usage of empirical antibiotics before admission or complicated clinical presentation. This technology is expected to play an important role in the precise application of antimicrobial drugs in the future.

No Evidence of Chronic Infection in a Metagenomic Sequencing Study of the Keratoconus Corneal Epithelium.

Objectives: This study aims to assess the presence of pathogenic microorganisms in the corneal epithelial layer of keratoconus patients. Methods: DNA was extracted from corneal epithelial samples procured from ten individual keratoconus eyes and three healthy controls. Metagenomic next-generation sequencing (mNGS) was performed to detect ocular microbiota using an agnostic approach. Results: Metagenomic sequencing revealed a low microbial read count in corneal epithelial samples derived from both keratoconus eyes (average: 530) and controls (average: 622) without a statistically significant difference (p = 0.29). Proteobacteria were the predominant phylum in both keratoconus and control samples (relative abundance: 72% versus 79%, respectively). Conclusions: The overall low microbial read count and the lack of difference in the relative abundance of different microbial species between keratoconus and control samples do not support the hypothesis that a chronic corneal infection is implicated in the pathogenesis of keratoconus. These findings do not rule out the possibility that an acute infection may be involved in the disease process as an initiating event.

Talaromyces marneffei: A challenging diagnosis in a kidney transplant patient.

Key Clinical Message: In addition to post-transplant lymphoproliferative disorders, it is necessary to be alert to the drug-resistant bacteria or fungal infection, especially Talaromyces marneffei, in kidney transplant patients who have failed antibiotic treatment and whose PET-CT indicates high metabolic mass in the transplanted kidney with a large number of other organs and lymph nodes. Abstract: Talaromyces marneffei (TM) is a rare pathogenic fungus that primarily affects individuals with compromised immune systems. Post-transplant lymphoproliferative disorders (PTLD) are serious complications that can occur after solid organ and cell transplantation. Both TM infection and PTLD can invade the monocyte-macrophage system and often manifest as extranodal masses. This case report describes a kidney transplant patient who presented with symptoms of frequent, urgent, and painful urination over 6 months. Pulmonary CT scans revealed multiple nodules, and PET-CT demonstrated enlarged lymph nodes in the lungs and the transplanted kidney. The clinical manifestations closely mimicked those of PTLD. The confirmation of TM was achieved through pathogen metagenomic next-generation sequencing and renal biopsy. Unfortunately, despite receiving treatment with antifungal agents, anti-infective therapy, the patient's condition did not respond favorably, ultimately resulting in their unfortunate demise due to COVID-19.

Metagenomic next-generation sequencing in the early diagnosis of leptospirosis infection presenting as acalculous cholecystitis and septic shock in a non-epidemic area after typhoons: A case report.

Key Clinical Message: Leptospirosis is an important zoonosis worldwide. Due to nonspecific clinical manifestation and poor recognition in non-epidemic area, there is often a delay in diagnosis and treatment. Early diagnosis from Metagenomic next-generation sequencing test is crucial for timely intervention. Abstract: We presented a case of a 19-year-old male patient who developed leptospirosis infection characterized by acalculous cholecystitis and septic shock after typhoon events. Metagenomic next-generation sequencing (mNGS) helped to early diagnose leptospirosis infection. Finally, the patient achieved full recovery following the antibiotic treatment in addition to supportive care and was discharged.

Metagenomic next-generation sequencing could play a pivotal role in validating the diagnosis of invasive mold disease of the central nervous system.

Background: Invasive mold diseases of the central nervous (CNS IMD) system are exceedingly rare disorders, characterized by nonspecific clinical symptoms. This results in significant diagnostic challenges, often leading to delayed diagnosis and the risk of misdiagnosis for patients. Metagenomic Next-Generation Sequencing (mNGS) holds significant importance for the diagnosis of infectious diseases, especially in the rapid and accurate identification of rare and difficult-to-culture pathogens. Therefore, this study aims to explore the clinical characteristics of invasive mold disease of CNS IMD in children and assess the effectiveness of mNGS technology in diagnosing CNS IMD. Methods: Three pediatric patients diagnosed with Invasive mold disease brain abscess and treated in the Pediatric Intensive Care Unit (PICU) of the First Affiliated Hospital of Zhengzhou University from January 2020 to December 2023 were selected for this study. Results: Case 1, a 6-year-old girl, was admitted to the hospital with "acute liver failure." During her hospital stay, she developed fever, irritability, and seizures. CSF mNGS testing resulted in a negative outcome. Multiple brain abscesses were drained, and Aspergillus fumigatus was detected in pus culture and mNGS. The condition gradually improved after treatment with voriconazole combined with caspofungin. Case 2, a 3-year-old girl, was admitted with "acute B-lymphoblastic leukemia." During induction chemotherapy, she developed fever and seizures. Aspergillus fumigatus was detected in the intracranial abscess fluid by mNGS, and the condition gradually improved after treatment with voriconazole combined with caspofungin, followed by "right-sided brain abscess drainage surgery." Case 3, a 7-year-old girl, showed lethargy, fever, and right-sided limb weakness during the pending chemotherapy period for acute B-lymphoblastic leukemia. Rhizomucor miehei and Rhizomucor pusillus was detected in the cerebrospinal fluid by mNGS. The condition gradually improved after treatment with amphotericin B combined with posaconazole. After a six-month follow-up post-discharge, the three patients improved without residual neurological sequelae, and the primary diseases were in complete remission. Conclusion: The clinical manifestations of CNS IMD lack specificity. Early mNGS can assist in identifying the pathogen, providing a basis for definitive diagnosis. Combined surgical treatment when necessary can help improve prognosis.

Case report: Multiple organ failure caused by Japanese spotted fever.

A 71-year-old male had disseminated multiple organ dysfunction syndrome (MODS). Following treatment with cefotaxime and piperacillin-tazobactam, his symptoms have worsened instead. Multiple organ failure caused by Japanese Spotted Fever (JSF) was diagnosed based on metagenomic next-generation sequencing (mNGS), we rapidly treated the patient with doxycycline. Thereafter, his symptoms gradually improved. In this report, we emphasized the importance of rapid microbial diagnostic tools and the early use of tetracyclines for the treatment of JSF.