Necrotizing fasciitis in haematological patients: a different scenario

The Etiology, Antibiotic Therapy and Outcomes of Bacteremic Skin and Soft-Tissue Infections in Onco-Hematological Patients

OBJECTIVES

to assess the current epidemiology, antibiotic therapy and outcomes of onco- hematological patients with bacteremic skin and soft-tissue infections (SSTIs), and to identify the risk factors for Gram-negative bacilli (GNB) infection and for early and overall mortality.

METHODS

episodes of bacteremic SSTIs occurring in cancer patients at two hospitals were prospectively recorded and retrospectively analyzed.

RESULTS

Of 164 episodes of bacteremic SSTIs, 53% occurred in patients with solid tumors and 47% with hematological malignancies. GNB represented 45.5% of all episodes, led by Pseudomonas aeruginosa (37.8%). Multidrug resistance rate was 16%. Inadequate empirical antibiotic therapy (IEAT) occurred in 17.7% of episodes, rising to 34.6% in those due to resistant bacteria. Independent risk factors for GNB infection were corticosteroid therapy and skin necrosis. Early and overall case-fatality rates were 12% and 21%, respectively. Risk factors for early mortality were older age, septic shock, and IEAT, and for overall mortality were older age, septic shock and resistant bacteria.

CONCLUSIONS

GNB bacteremic SSTI was common, particularly if corticosteroid therapy or skin necrosis. IEAT was frequent in resistant bacteria infections. Mortality occurred mainly in older patients with septic shock, resistant bacteria and IEAT. These results might guide empirical antibiotic therapy in this high-risk population.

Necrotizing soft tissue infections in critically ill neutropenic patients: a French multicentre retrospective cohort study

BACKGROUND

Necrotizing soft tissue infections (NSTIs) are rare life-threatening bacterial infections. Few data are available regarding neutropenic patients with NSTIs. Our objectives were to describe the characteristics and management of neutropenic patients with NSTIs in intensive care units (ICUs). We conducted a retrospective multicentre cohort study in 18 ICUs between 2011 and 2021. Patients admitted with NSTIs and concomitant neutropenia at diagnosis were included and compared to non-neutropenic patients with NSTIs. The relationship between therapeutic interventions and outcomes was assessed using Cox regression and propensity score matching.

RESULTS

76 neutropenic patients were included and compared to 165 non-neutropenic patients. Neutropenic patients were younger (54 ± 14 vs 60 ± 13 years, p = 0.002) and had less lower limb (44.7% vs 70.9%, p < 0.001) and more abdomino-perineal NSTIs (43.4% vs 18.8%, p < 0.001). Enterobacterales and non-fermenting gram-negative bacteria were the most frequently isolated microorganisms in neutropenic patients. In-hospital mortality was significantly higher in neutropenic than in non-neutropenic patients (57.9% vs 28.5%, p < 0.001). Granulocyte colony-stimulating factor (G-CSF) administration was associated with a lower risk of in-hospital mortality in univariable Cox (hazard ratio (HR) = 0.43 95% confidence interval (CI) [0.23-0.82], p = 0.010) and multivariable Cox (adjusted HR = 0.46 95% CI [0.22-0.94], p = 0.033) analyses and after overlap propensity score weighting (odds ratio = 0.25 95% CI [0.09; 0.68], p = 0.006).

CONCLUSIONS

Critically ill neutropenic patients with NSTIs present different clinical and microbiological characteristics and are associated with a higher hospital mortality than non-neutropenic patients. G-CSF administration was associated with hospital survival.

Reconstruction of the Scrotum With Bilateral Gracilis Muscle Rotational Flaps in a Patient With Acute Myeloid Leukemia Complicated by Fournier’s Gangrene

We describe the case of a 43-year-old male diagnosed with acute myeloid leukemia complicated by Fournier’s gangrene. Multiple debridements led to the complete effacement of the scrotum, with 360 degrees of exposed testes and a narrow base of suspension. It was decided to reconstruct the scrotum using bilateral gracilis muscle rotational flaps, followed by split-thickness skin grafting from the thigh. The gracilis muscle as a donor flap allowed for the protection and support of the testes and suspensory tissue while achieving an aesthetically pleasing result that resembled the normal scrotum. We hope providers will consider this reconstructive method in future patients who present with similar extensive effacement of the scrotal tissue.

Fournier's Gangrene in Patients with Oncohematological Diseases: A Systematic Review of Published Cases

Patients suffering from hematological malignancies are at increased risk of Fournier's gangrene (FG) due to immunosuppression caused by the disease itself or by disease-related treatments. A systematic review of PubMed, ISI Web of Knowledge, and Scopus databases was performed in June 2021. We included full papers that met the following criteria: original research, human studies, and describing clinical presentation, treatment, and outcomes of FG in patients with oncohematological diseases. We identified 35 papers published from 1983 to 2021 involving 44 patients (34 males, 8 females) aged between 4 days and 83 years. The most common malignant hematological disorders were acute myeloid leukemia (n = 21) and acute lymphocytic leukemia (n = 9). In 10 patients FG represented the first presentation of hematological malignancy. Scrotum (n= 27) and perineum (n = 11) were the sites most commonly involved. Pseudomonas aeruginosa (n = 21) and Escherichia coli (n = 6) were the most commonly isolated microorganisms. Surgery was performed in 39 patients. Vacuum-assisted closure and hyperbaric oxygen therapy were adopted in 4 and in 3 patients, respectively. Recovery was achieved in 30 patients. FG-related mortality was observed in 11 patients. FG should be carefully considered in patients with oncohematological diseases.

Necrotizing fasciitis caused by mono-bacterial gram-negative infection with E. coli - the deadliest of them all: A case series and review of the literature

Introduction

Unlike other skin and soft tissue infections, necrotizing fasciitis (NF) is a very rare but potentially fatal condition. Common organisms causing NF are poly-microbial (type I) infection with mixed organisms and mono-bacterial gram-positive infection with mainly streptococci (type II). Mono-bacterial gram-negative NF is a rare form of NF that is not included in the current classification.

Case series

We report four cases of mono-bacterial gram-negative NF caused by E. coli. All patients presented in septic shock and showed landscape-like skin necrosis and pain out of proportion. Radical debridement and escalation of antibiotic treatment was performed in all patients. Short-term survival was 50%. Two patients died of multiorgan failure. Two patients survived short term: One patient was amputated through the knee but died six months later of metastatic prostate cancer. One patient was covered with split thickness skin grafts and died three months later of catheter-associated sepsis with endocarditis.

Discussion

Recent findings suggest adding a type III fasciitis, which is caused by mono-bacterial gram-negative organisms. As patients are getting older with even more comorbidities, mono-bacterial gram-negative NF will be an increasing problem for physicians treating soft tissue and skin infections.

In oncologic diseases, liver cirrhosis, renal diseases or otherwise immunocompromised patients, mono-bacterial gram-negative NF with E. coli is underestimated. Therefore, in these patients, antibiotic treatment should cover Gram-negative organisms including E. coli. However even with adjusted antibiotic treatment and radical debridement, the short-term survival and long-term outcome are poor.

Skin and Soft Tissue Infections in Non-Human Immunodeficiency Virus Immunocompromised Hosts

Skin and soft tissue infections among the non-human immunodeficiency virus infected immunosuppressed population are a serious and growing concern. Many pathogens can cause cutaneous infections in these patients owing to the highly varied and profound immune deficits. Although patients can be infected by typical organisms, the diversity and antimicrobial-resistant nature of the organisms causing these infections result in significant morbidity and mortality. The diagnostic approach to these infections in immunocompromised hosts can differ dramatically depending on the potential causative organisms. An understanding of new immunosuppressive treatments and evolving antimicrobial resistance patterns are required to optimally manage these difficult cases.