Cystic fibrosis (CF) is a genetic disease that affects the lung, pancreas, and other organs caused by the presence of biallelic CF-causing variants in the cystic fibrosis conductance regular gene (CFTR). CFTR variants can also be found in CFTR-related disorders (CFTR-RD), which present milder symptoms. Increasing access to next-generation sequencing has demonstrated that both CF and CFTR-RD have a broader array of genotypes than formerly thought. Here we present three patients who carry the most common CFTR pathogenic variant - F508del - but express a wide array of phenotypes. These cases open discussion on the role of concurrent variants in CFTR, the importance of early diagnosis and treatment, and the contribution of lifestyle factors in CF and CFTR-RD presentation.

Infections with nontuberculous mycobacteria (NTM) are increasing in prevalence worldwide, and this group of organisms is emerging as significant clinical pathogens. We present a case of a 58-year-old female with persistent furuncles of the breast who was found to have an NTM infection. This case is unique for the lack of risk factors for NTM in the patient's history, the location of the infection in the breast, and the close cooperation needed across disciplines to arrive at the diagnosis. This multi-disciplinary discussion considers the classic clinical presentation of NTM, it is a characteristic morphological appearance on histopathology, the differential diagnosis, treatment, and the ultimate outcome of the case. This case report and discussion will assist both clinicians and pathologists in the diagnosis of this important infectious disease.

Thromboembolism is known to be a multifactorial event that is impacted by various genetic and environmental factors. The genetics society's recommended name for this variant is c.*97G>A (this is the nomenclature we need to use in the patient report). However, people have been using legacy names c.20210G>A or G20210A (so these are common names). One of the most common genetic variants associated with inherited thrombophilias, F2 c.20210G>A is acknowledged to be a weak but significant risk factor for thromboembolism. However, its clinical presentation has been described as phenotypically heterogeneous. We present two rare cases with homozygous F2 c.20210G>A variant, one of which also carries a heterozygous variant in coagulation factor V gene F5, c.1601G>A (p.Arg534Gln; commonly known as factor V Leiden). We described the clinical courses of these two cases and discussed F2 c.20210G>A and factor V Leiden as genetic risk factors in thromboembolism, the role of provoking factors, such as surgery and malignancy, and the management of such patients.