Diarrhea caused by opportunistic intestinal protozoa is a common problem in HIV infection. We aimed to establish the prevalence of Cryptosporidium, misrosporidia, and Isospora in HIV-infected people using a systematic review and meta-analysis, which is central to developing public policy and clinical services. We searched PubMed, ScienceDirect, Google Scholar, Embase, Chinese Web of Knowledge, Wanfang, and Chongqing VIP databases for studies reporting Cryptosporidium, microsporidia, or Isospora infection in HIV-infected people. We extracted the numbers of people with HIV and protozoa infection, and estimated the pooled prevalence of parasite infection by a random effects model. Our research identified 131 studies that reported Cryptosporidium, microsporidia, and Isospora infection in HIV-infected people. We estimated the pooled prevalence to be 14.0% (3283/43,218; 95% CI: 13.0–15.0%) for Cryptosporidium, 11.8% (1090/18,006; 95% CI: 10.1–13.4%) for microsporidia, and 2.5% (788/105,922; 95% CI: 2.1–2.9%) for Isospora. A low prevalence of microsporidia and Isospora infection was found in high-income countries, and a high prevalence of Cryptosporidium and Isospora infection was found in sub-Saharan Africa. We also detected a high prevalence of Cryptosporidium, microsporidia, and Isospora infection in patients with diarrhea. Sensitivity analysis showed that three studies significantly affect the prevalence of Isospora, which was adjusted to 5.0% (469/8570; 95% CI: 4.1–5.9%) by excluding these studies. Our findings suggest that HIV-infected people have a high prevalence of Cryptosporidium, microsporidia, and Isospora infection in low-income countries and patients with diarrhea, especially in sub-Saharan Africa, reinforcing the importance of routine surveillance for opportunistic intestinal protozoa in HIV-infected people.

Tick-borne rickettsioses are considered important emerging zoonoses worldwide, but their etiological agents, rickettsiae, remain poorly characterized in northeastern China, where many human cases have been reported during the past several years. Here, we determined the characteristics of Rickettsia spp. infections in ticks in this area. Ticks were collected by flagging vegetation from Jilin and Heilongjiang provinces of northeastern China followed by morphological identification. The presence of Rickettsia spp. in ticks was detected by PCR targeting the 23S-5S ribosomal RNA intergenic spacer, citrate synthase (gltA) gene, and 190-kDa outer membrane protein gene (ompA). The newly-generated sequences were subjected to phylogenetic analysis using the software MEGA 6.0. The overall infection rate of Rickettsia spp. was 6.12 %. Phylogenetic analyses based on the partial gltA and ompA genes demonstrated that rickettsiae detected in the ticks belong to four species, including “Candidatus Rickettsia tarasevichiae”, Rickettsia heilongjiangensis, Rickettsia raoultii, and a potential new species isolate. The associated tick species were also identified, i.e. Dermacentor nuttalli and Dermacentor silvarum for R. raoultii, Haemaphysalis concinna and Haemaphysalis longicornis for R. heilongjiangensis, and Ixodes persulcatus for “Ca. R. tarasevichiae”. All Rickettsia spp. showed significantly high infection rates in ticks from Heilongjiang when compared to Jilin Province. Rickettsia heilongjiangensis, R. raoultii and “Ca. R. tarasevichiae” are widely present in the associated ticks in northeastern China, but more prevalent in Heilongjiang Province. The data of this study increase the information on the distribution of Rickettsia spp. in northeastern China, which have important public health implications in consideration of their recent association with human diseases.

Background: Pseudomyxoma peritonei (PMP) is a rare peritoneal malignancy with limited genomic data across different biospecimen types. The extent to which ascites and plasma reflect tissue-detected genomic alterations remains incompletely characterized. This study compared genomic profiles across tumor tissue, ascites, and plasma and explored KRAS-defined molecular features in PMP. Methods: Sixty patients with pathologically confirmed PMP were retrospectively included. Next-generation sequencing (NGS) data were available from tumor tissue in 57 patients, ascites in 40, and plasma in 28, with overlapping specimen availability. Cross-specimen genomic concordance was evaluated in 37 patients with matched tissue–ascites samples, including 28 patients with matched tissue, ascites, and plasma. Exploratory analyses were performed to characterize genomic and pathway-level features across KRAS-defined subgroups. Results: In tumor tissue, KRAS (66.7%), GNAS (31.6%), and TP53 (21.1%) were the most frequently altered genes. Among 28 patients with matched tissue, ascites, and plasma, patient-level concordance was 35.7%. At the mutation level, ascites showed higher tissue-referenced positive percentage agreement (PPA) than plasma (93.1% vs. 36.2%). In the expanded cohort of 37 matched tissue–ascites pairs, ascites achieved a tissue-referenced PPA of 94.2% and revealed additional alterations not detected in the corresponding tissue samples. Exploratory KRAS mutation stratification identified G12D (35.0%), G12X (32.5%), and KRAS-wild-type (wt) (17.5%) tumors as the predominant subgroups. KRAS-mutant tumors harbored more detected genomic alterations and potentially clinically actionable alterations than KRAS-wt tumors. Wnt and PI3K pathway alterations were more commonly observed in the G12D and G12X subgroups, respectively, whereas canonical oncogenic pathway alterations were less frequent in KRAS-wt tumors. Conclusions: PMP exhibits substantial genomic heterogeneity across patients and biospecimen types. Ascites cfDNA showed high concordance with tissue and captured additional genomic alterations, suggesting that ascitic fluid may serve as a complementary source for molecular profiling in PMP. KRAS-defined subgroups exhibited distinct genomic characteristics, although their clinical relevance requires further validation in larger, well-characterized cohorts.