Mycobacterium kansasii infection with dermatologic manifestations

The Mycobacterium kansasii species comprises six subtypes that were recently classified into six closely related species; Mycobacterium kansasii (formerly M. kansasii subtype 1), Mycobacterium persicum (subtype 2), Mycobacterium pseudokansasii (subtype 3), Mycobacterium ostraviense (subtype 4), Mycobacterium innocens (subtype 5) and Mycobacterium attenuatum (subtype 6). Together with Mycobacterium gastri, they form the M. kansasii complex. M. kansasii is the most frequent and most pathogenic species of the complex. M. persicum is classically associated with diseases in immunosuppressed patients, and the other species are mostly colonizers, and are only very rarely reported in ill patients. Comparative genomics was used to assess the genetic determinants leading to the pathogenicity of members of the M. kansasii complex. The genomes of 51 isolates collected from patients with and without disease were sequenced and compared with 24 publicly available genomes. The pathogenicity of each isolate was determined based on the clinical records or public metadata. A comparative genomic analysis showed that all M. persicum, M. ostraviense, M innocens and M. gastri isolates lacked the ESX-1-associated EspACD locus that is thought to play a crucial role in the pathogenicity of M. tuberculosis and other non-tuberculous mycobacteria. Furthermore, M. kansasii was the only species exhibiting a 25-Kb-large genomic island encoding for 17 type-VII secretion system-associated proteins. Finally, a genome-wide association analysis revealed that two consecutive genes encoding a hemerythrin-like protein and a nitroreductase-like protein were significantly associated with pathogenicity. These two genes may be involved in the resistance to reactive oxygen and nitrogen species, a required mechanism for the intracellular survival of bacteria. Three non-pathogenic M. kansasii lacked these genes likely due to two distinct distributive conjugal transfers (DCTs) between M. attenuatum and M. kansasii, and one DCT between M. persicum and M. kansasii. To our knowledge, this is the first study linking DCT to reduced pathogenicity.

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A rare case of fat embolism syndrome secondary to abdominal liposuction and gluteal fat infiltration

Journal of Surgical Case Reports ◽

10.1093/jscr/rjaa441 ◽

2020 ◽

Vol 2020 (12) ◽

Author(s):

Salvador Recinos ◽

Sabrina Barillas ◽

Alejandra Rodas ◽

Javier Ardebol

Keyword(s):

Right Ventricular Dysfunction ◽

Signs And Symptoms ◽

Fat Embolism ◽

Fat Infiltration ◽

Fat Embolism Syndrome ◽

Embolism Syndrome ◽

Threatening Condition ◽

Life Threatening ◽

Bone Marrow Harvesting ◽

Dermatologic Manifestations

Abstract Fat embolism syndrome (FES) is a rare, life-threatening condition habitually associated with traumatic events such as fractures and, less commonly, burns, liposuction and bone marrow harvesting and transplant [ 1]. The biochemical theory for this condition suggests that fat droplets embolize and convert into fatty acids, eventually leading to toxic injury and inflammation, which results in increased vascular permeability, edema and hemorrhage [ 2]. FES may have an asymptomatic interval lasting 12–72 hours after the insult; however, in some cases, signs have also been seen intraoperatively. Pulmonary signs and symptoms are customarily the earliest and manifest in 75% of patients. Nevertheless, neurologic and dermatologic manifestations are also characteristic, and most severe cases could perhaps present with disseminated intravascular coagulation, right ventricular dysfunction, shock or death. The following case consists of a 37-year-old patient that presented with fat embolism syndrome during liposuction and gluteal fat infiltration.

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