Gonadal and gonosomal mosaicism describe phenomena in which a seemingly healthy individual carries a genetic variant in a subset of their gonadal tissue or gonadal and somatic tissue(s), respectively, with risk of transmitting the variant to their offspring. In families with one or more affected offspring, occurrence of the same apparently de novo variants can be an indicator of mosaicism in either parent. Panel-based deep sequencing has the capacity to detect low-level mosaic variants with coverage exceeding the typical limit of detection provided by current, readily available sequencing techniques. In this study, we report three families with more than one affected offspring with either confirmed or apparent parental gonosomal or gonadal mosaicism for PIK3CD pathogenic variants. Data from targeted deep sequencing was suggestive of low-level maternal gonosomal mosaicism in Family 1. Through this approach we did not detect pathogenic variants in PIK3CD from parental samples in Family 2 and Family 3. We conclude that mosaicism was likely confined to the maternal gonads in Family 2. Subsequent long-read genome sequencing in Family 3 showed that the paternal chromosome harbored the pathogenic variant in PIK3CD in both affected children, consistent with paternal gonadal mosaicism. Detection of parental mosaic variants enables accurate risk assessment, informs reproductive decision-making, and provides helpful context to inform clinical management in families with PIK3CD pathogenic variants.

BACKGROUND: Plastic bronchitis (PB) is an uncommon and severe acute respiratory ailment characterized by the formation of casts in the trachea or bronchial tree. Some instances have been linked to human bocavirus (HBoV) infections.
METHODS: In this report, we present a case of PB secondary to HBoV1 infection in a previously healthy pediatric patient. A 17-month-old male was admitted due to respiratory distress following 2 days of cough and fever. A preadmission chest X-ray revealed atelectasis of the left lung. Emergency electronic bronchoscopy and foreign body forceps were employed to remove casts, leading to improved breathing. High-throughput next-generation sequencing detected only HBoV1. A subsequent electronic bronchoscopy 2 days later showed no casts.
CONCLUSIONS: PB associated with HBoV1 infection should be considered in children experiencing acute respiratory distress, and a second bronchoscopy intervention may not be necessary in cases related to HBoV1.

BRCA genes have well-known associations with breast and ovarian cancers. However, variations in the BRCA gene, especially germline variations, have also been reported in colorectal cancer (CRC). We present the case of a rectal cancer with a germline BRCA1 variation inherited from the paternal side. A 39-year-old male was admitted with rectal cancer. The patient underwent surgical resection and the pathologic diagnosis was adenocarcinoma. Next-generation sequencing was performed and a BRCA1 variant was detected. Reviewing the public database and considering the young age of the patient, the variant was suggested to be germline. The patient\'s father had had prostate cancer and next-generation sequencing testing revealed an identical BRCA1 variant. In the BRCA cancer group, there is relatively little attention paid to male cancers. The accumulation of male CRC cases linked to BRCA variations may help clarify the potential pathological relationship between the two.

BACKGROUND: SARS-CoV-2 is responsible for the ongoing global pandemic, and the continuous emergence of novel variants threatens fragile populations, such as immunocompromised patients. This subgroup of patients seems to be seriously affected by intrahost viral changes, as the pathogens, which are keen to cause replication inefficiency, affect the impaired immune system, preventing efficient clearance of the virus. Therefore, these patients may represent an optimal reservoir for the development of new circulating SARS-CoV-2 variants. The following study aimed to investigate genomic changes in SARS-CoV-2-positive immunocompromised patients over time.
METHODS: SARS-CoV-2-positive nasopharyngeal swabs were collected at different time points for each patient (patient A and patient B), extracted and then analyzed through next-generation sequencing (NGS). The resulting sequences were examined to determine mutation frequencies, describing viral evolution over time.
METHODS: Patient A was a 53-year-old patient with onco-hematological disease with prolonged infection lasting for 51 days from May 28th to July 18th, 2022. Three confirmed SARS-CoV-2-positive samples were collected on May 28th, June 15th and July 4th. Patient B was 75 years old and had onco-hematological disease with prolonged infection lasting for 146 days. Two confirmed positive SARS-CoV-2 samples were collected at the following time points: May 21st and August 18th.
CONCLUSIONS: Heat map construction provided evidence of gain and/or loss of mutations over time for both patients, suggesting within-host genomic evolution of the virus. In addition, mutation polymorphisms and changes in the SARS-CoV-2 lineage were observed in Patient B. Sequence analysis revealed high mutational pattern variability, reflecting the high complexity of viral replication dynamics in fragile patients.

(1) Background: The study of the microbiome is crucial for its role in major systemic diseases, in particular the oral and gut microbiota. In recent years, the study of microorganisms correlated, for example, with neurodegenerative disease has increased the prospect of a possible link between gut microbiota and the brain. Here, we report a new case concerning a patient who was initially evaluated genetically for dementia and late-onset dyskinesia, and later tested with 16S metagenomics sequencing. (2) Methods: Starting from a buccal swab, we extracted bacterial DNA and then we performed NGS metagenomics sequencing based on the amplification of the hypervariable regions of the 16S rRNA gene in bacteria. (3) Results: The sequencing revealed the presence of the Spirochaetes phylum, a pathogenic bacterium generally known to be capable of migrating to the Central Nervous System. (4) Conclusions: Oral infections, as our results suggest, could be possible contributing factors to various neurodegenerative conditions.

BACKGROUND: Type 2B von Willebrand disease (VWD) is a less common subtype and is difficult to diagnose. This case report and literature review highlights a rare neonatal onset of type 2B VWD initially misdiagnosed as neonatal alloimmune thrombocytopenia (NAIT).
METHODS: The neonate presented with severe thrombocytopenia and was unresponsive to NAIT treatments. Genetic testing was conducted because of the unclear family history of thrombocytopenia.
RESULTS: Next-generation sequencing revealed a p.Arg1306Trp von Willebrand factor variant, confirming type 2B VWD.
CONCLUSIONS: This study underscores the critical role of genetic testing in diagnosing challenging cases of neonatal thrombocytopenia, irrespective of family history, and aims to elucidate the clinical manifestations and course of neonatal onset type 2B VWD.

本文报道1例发生于中年男性的由单纯疱疹病毒2型感染所致的急性咽喉炎。患者男，41岁，因“剧烈咽痛、高热2 d”就诊。初始血常规检查结果符合细菌性感染特征，但给予敏感抗生素治疗5 d无效，进一步完善相关病原学抗体检查，结果均为阴性。后采用靶向测序（targeted Next Generation Sequencing，tNGS）明确诊断感染病原体为单纯疱疹病毒2型（多引发生殖器感染，咽喉部感染少见），给予针对性抗病毒药物治疗后患者感染相关临床症明显好转，1周后痊愈。.

BACKGROUND: Angiostrongyliasis cantonensis is a severe yet rare parasitic infection caused by the larvae of Angiostrongylus cantonensis. The primary characteristic feature of this foodborne illness in humans is eosinophilic meningitis. Recently, there has been a gradual increase in reported cases globally. Due to the lack of typical clinical symptoms, signs, and specific laboratory tests, early diagnosis of this disease poses significant challenges. Failure to diagnose and treat this condition promptly can result in fatalities.
METHODS: We present the case of a 13-year-old male patient who initially presented with fever and headache. The patient was preliminarily diagnosed with bacterial meningitis and received treatment with antibacterial drugs. However, the patient\'s condition worsened, and he developed progressive consciousness disturbances. Eventually, metagenomic next-generation sequencing (mNGS) testing of cerebrospinal fluid samples indicated Angiostrongylus cantonensis infection. Following treatment with albendazole and prednisone, the patient made a full recovery. We include this case report as part of a literature review to emphasize the potential applications of mNGS in the early diagnosis of Angiostrongyliasis cantonensis.
CONCLUSIONS: mNGS technology plays a crucial role in the diagnosis of angiostrongyliasis cantonensis. As this technology continues to evolve and be applied, we believe it will play an increasingly important role in diagnosing, treating, and monitoring angiostrongyliasis cantonensis.

Lung cancer is the leading cause of cancer mortality worldwide. Fortunately, the advent of precision medicine, which includes targeted therapy and immunotherapy, offers hope. However, identifying specific mutations is imperative before initiating precise medications. Traditional methods, such as real-time PCR examination of individual mutations, are time-consuming. Contemporary techniques, such as tissue- and plasma-based next-generation sequencing (NGS), allow comprehensive genome analysis concurrently. Notably, plasma-based NGS has a shorter turnaround time (TAT) and thus a shorter time-to-treatment (TTT). In this case report, we demonstrate the benefits of plasma-based NGS before pathological diagnosis in a patient with image-suspected non-small cell lung cancer (NSCLC). An 82-year-old Taiwanese woman presented with lower back pain persisting for one month and left-sided weakness for two weeks. Whole-body computed tomography (CT) revealed lesions suspicious for brain and bone metastases, along with a mass consistent with a primary tumor in the left upper lobe, indicative of advanced NSCLC with T4N3M1c staging. The patient underwent a bronchoscopic biopsy on Day 0, and the preliminary report that came out on Day 1 was suggestive of metastatic NSCLC. Blood was also collected for plasma-based NGS on Day 0. The patient was Coronavirus disease 2019-positive and was treated with molnupiravir on Day 6. On Day 7, pathology confirmed pulmonary adenocarcinoma, and the results of plasma-based NGS included EGFR L858R mutation. The patient was started on targeted therapy (afatinib) on Day 9. Unfortunately, the patient died of hypoxic respiratory failure on Day 26, a complication of underlying viral infection. Plasma-based NGS offers a rapid and efficient means of mutation detection in NSCLC, streamlining treatment initiation and potentially improving the negative emotions of patients. Its utility, particularly in regions with a high prevalence of specific mutations, such as EGFR alterations in East Asian populations, highlights its relevance in guiding personalized therapy decisions.

The case presents a 47-year-old man with sudden abdominal pain and fever, but the cause was uncertain. Through metagenomic next-generation sequencing (mNGS) and detecting Q fever antibodies in serum, along with the patient\'s clinical and epidemiological history, a precise diagnosis was made, enabling timely and proper treatment.