N Gene Target Failure (NGTF) for detection of Omicron: a way out for the "stealth" too?

S-gene target failure (SGTF) is neither specific nor accurate for identification of Omicron lineage of SARS-CoV-2. We observed N-gene target failure (NGTF) in 402 out of 412 SARS-CoV2 positive cases from December to mid-January 2022 using a commercially available assay. This phenomenon was not observed with more than 15,000 cases tested previously. We sequenced the genome of five samples with NGTF and compared these results with six cases where NGTF was not seen. We confirm that cases with NGTF were the Omicron lineage while cases with preserved N-gene amplification belonged to Delta lineage. We discovered that the ERS31-33 deletion (nucleotide 28362-28370del) overlaps with N gene probe used, explaining NGTF. As the stealth Omicron variant also harbors ERS31-33 deletion, this approach will work for the detection of stealth Omicron variant as well. We suggest that NGTF can be used as a low cost, rapid screening strategy for detection of Omicron.

Disseminated intravascular coagulation presenting as symmetrical peripheral gangrene: a case report.

INTRODUCTION: Plasmodium vivax was traditionally thought to be benign; however, nowadays it presents with a myriad of systemic complications like cerebral malaria, acute respiratory distress syndrome, acute kidney injury, acute pancreatitis, hepatic dysfunction, and disseminated intravascular coagulation, which were earlier attributed only to Plasmodium falciparum malaria. Here we report a case of a middle-aged man who presented with disseminated intravascular coagulation manifesting as symmetrical peripheral gangrene. What makes this case more interesting is that the malaria isolated was Plasmodium vivax instead of Plasmodium falciparum. Such findings were previously reported, but this is the first case where the patient was managed conservatively with antimalarial drugs without the need for amputation, which focuses on the very important role of early diagnosis and timely management. CASE PRESENTATION: A 44-year-old Indian man from north India presented with history of fever of 2 days' duration with severely painful cold extremities. No pulse could be recorded on examination. A diagnosis of symmetrical peripheral gangrene was made. During the etiological evaluation, Plasmodium vivax malaria was found leading to disseminated intravascular coagulation causing this complication. He was started on artesunate and lumefantrine combination therapy and he recovered completely without the requirement of amputation. CONCLUSION: This case highlights the non-benign nature of Plasmodium vivax and its emerging complications. Also it correlates symmetrical peripheral gangrene with Plasmodium vivax malaria. It also emphasizes the importance of timely diagnosis and intervention to reduce mortality and morbidity.