Objectives: To discuss the presentation and management of infants with arhinia or congenital absence of the nose. Methods: This case report describes an infant with arhinia that was diagnosed prenatally. In addition to a discussion of the case, a review of the literature was completed to define appropriate postnatal work-up and management. Results: The patient is a term male infant, diagnosed with arhinia on ultrasound and magnetic resonance imaging (MRI) performed at 21-weeks gestational age. Upon birth, the patient was subsequently intubated, followed by tracheostomy due to complete nasal obstruction. Through a genetics evaluation, the patient was found to be heterozygous for the SMCHD1 gene, with hypomethylation at the D4Z4 locus. Plans for reconstruction will be based on future imaging and the development of any nasal patency, however, the patient’s family plans to utilize a prosthetic nose until the patient is older. Conclusion: Arhinia is a rare condition causing respiratory distress in the neonatal period. While stabilization of the airway is the first priority, further management is not clearly defined given the rarity of the malformation. This case discusses stabilization of the airway with a review of treatment and reconstructive options.

Several recent studies have illustrated the beneficial effects of living in an enriched environment on improving human disease. In mice, environmental enrichment (EE) reduces tumorigenesis by activating the mouse immune system, or affects tumor bearing animal survival by stimulating the wound repair response, including improved microbiome diversity, in the tumor microenvironment. Provided here is a detailed procedure to assess the effects of environmental enrichment on the biodiversity of the microbiome in a mouse colon tumor model. Precautions regarding animal breeding and considerations for animal genotype and mouse colony integration are described, all of which ultimately affect microbial biodiversity. Heeding these precautions may allow more uniform microbiome transmission, and consequently will alleviate non-treatment dependent effects that can confound study findings. Further, in this procedure, microbiota changes are characterized using 16S rDNA sequencing of DNA isolated from stool collected from the distal colon following long-term environmental enrichment. Gut microbiota imbalance is associated with the pathogenesis of inflammatory bowel disease and colon cancer, but also of obesity and diabetes among others. Importantly, this protocol for EE and microbiome analysis can be utilized to study the role of microbiome pathogenesis across a variety of diseases where robust mouse models exist that can recapitulate human disease.

Several recent studies have illustrated the beneficial effects of living in an enriched environment on improving human disease. In mice, environmental enrichment (EE) reduces tumorigenesis by activating the mouse immune system, or affects tumor bearing animal survival by stimulating the wound repair response, including improved microbiome diversity, in the tumor microenvironment. Provided here is a detailed procedure to assess the effects of environmental enrichment on the biodiversity of the microbiome in a mouse colon tumor model. Precautions regarding animal breeding and considerations for animal genotype and mouse colony integration are described, all of which ultimately affect microbial biodiversity. Heeding these precautions may allow more uniform microbiome transmission, and consequently will alleviate nontreatment dependent effects that can confound study findings. Further, in this procedure, microbiota changes are characterized using 16S rDNA sequencing of DNA isolated from stool collected from the distal colon following long-term environmental enrichment. Gut microbiota imbalance is associated with the pathogenesis of inflammatory bowel disease and colon cancer, but also of obesity and diabetes among others. Importantly, this protocol for EE and microbiome analysis can be utilized to study the role of microbiome pathogenesis across a variety of diseases where robust mouse models exist that can recapitulate human disease. Video LinkThe video component of this article can be found at https://www.jove.com/video/57182/ 9,10,11. One example is animal integration, where animals must be stably integrated into the mouse colony, therefore normalizing genetic background and diet composition, to avoid non-treatment related effects. Further, many EE studies have been completed