Acute bacterial skin infections and cellulitis

Recent Advances in Pharmaceutical Approaches of Antimicrobial Agents for Selective Delivery in Various Administration Routes

Globally, the increase of pathogenic bacteria with antibiotic-resistant characteristics has become a critical challenge in medical treatment. The misuse of conventional antibiotics to treat an infectious disease often results in increased resistance and a scarcity of effective antimicrobials to be used in the future against the organisms. Here, we discuss the rise of antimicrobial resistance (AMR) and the need to combat it through the discovery of new synthetic or naturally occurring antibacterial compounds, as well as insights into the application of various drug delivery approaches delivered via various routes compared to conventional delivery systems. AMR-related infectious diseases are also discussed, as is the efficiency of various delivery systems. Future considerations in developing highly effective antimicrobial delivery devices to address antibiotic resistance are also presented here, especially on the smart delivery system of antibiotics.

Long-Term Benzathine Penicillin Prophylaxis Lasting for Years Effectively Prevents Recurrence of Dermato-Lymphangio-Adenitis (Cellulitis) in Limb Lymphedema

Background: The lymphedema-affected limbs are predisposed to acute and, subsequently, chronic dermato-lymphangio-adenitis (DLA) episodes in around 40%-50% of cases, irrespective of what the primary etiological factor is for the development of this condition. DLA is of bacterial etiology, and it needs antibiotic control and prevention of recurrence. Aim: To follow the effects of years-long continuous no-break administration of benzathine penicillin on the recurrence of acute DLA episodes. Methods and Results: Two hundred thirty-one patients were affected with lymphedema of lower and upper limbs. The mean duration of lymphedema was 10.2 ± 7.3 (range 2-30) years, and the number of DLA attacks/patient was 3.3 ± 3.2 (range 1-10). The total number of DLA episodes was 805. Benzathine penicillin injections 1,200,000 units were given i.m. at 14-21 days intervals (mean 18 ± 9 days) with short accidental breaks only. The period of therapy was 39.2 ± 38.7 (median 32) months. Recurrence occurred in 23 out of 231 (10%) (p < 0.01). There were 42 DLA incidents compared with 805 before introduction of therapy (5.2%) patients (hazard ratio 0.05, 95% confidence interval 0.034-0.079) (p < 0.01). Among patients with recurrence, there was a decrease of DLA episodes from 6.2% ± 3.6% to 1.7% ± 1.0%/patient. There were no differences in effectiveness of penicillin prophylaxis between etiological groups, depending on stages of lymphedema. Conclusions: Long-term years-long benzathine penicillin prophylaxis is extremely effective in prevention of DLA recurrence. It can be applied for years with no breaks, without clinical side-effects, and raising resistance to antibiotics. Microbial colonization and evoked inflammatory reaction of hosts should be controlled from the first symptoms of lymph stasis, irrespective of the etiology of lymphedema.

Intracellular Streptococcal Uptake and Persistence: A Potential Cause of Erysipelas Recurrence

Erysipelas is a severe streptococcal infection of the skin primarily spreading through the lymphatic vessels. Penicillin is the treatment of choice. The most common complication consists in relapses which occur in up to 40% or more of patients despite appropriate antibiotic treatment. They cause lymphatic damage resulting in irreversible lymphedema and ultimately elephantiasis nostras and lead to major health restrictions and high socio-medical costs. Prevention of relapses is an unmet need, because even long-term prophylactic penicillin application does eventually not reduce the risk of recurrence. In this article we assess risk factors and causes of erysipelas recurrence. A systematic literature search for clinical studies addressing potential causes and measures for prevention of erysipelas recurrence was combined with a review of experimental and clinical data assessing the ability and clinical relevance of streptococci for intracellular uptake and persistence. The literature review found that venous insufficiency, lymphedema, and intertrigo from fungal infections are considered to be major risk factors for recurrence of erysipelas but cannot adequately explain the high recurrence rate. As hitherto unrecognized likely cause of erysipelas relapses we identify the ability of streptococci for intracellular uptake into and persistence within epithelial and endothelial cells and macrophages. This creates intracellular streptococcal reservoirs out of reach of penicillins which do not reach sufficient bactericidal intracellular concentrations. Incomplete streptococcal elimination due to intracellular streptococcal persistence has been observed in various deep tissue infections and is considered as cause of relapsing streptococcal pharyngitis despite proper antibiotic treatment. It may also serves as endogenous infectious source of erysipelas relapses. We conclude that the current antibiotic treatment strategies and elimination of conventional risk factors employed in erysipelas management are insufficient to prevent erysipelas recurrence. The reactivation of streptococcal infection from intracellular reservoirs represents a plausible explanation for the frequent occurrence erysipelas relapses. Prevention of erysipelas relapses therefore demands for novel antibiotic strategies capable of eradicating intracellular streptococcal persistence.

Risk factors and complications of lower limb cellulitis in Africa: a systematic review

OBJECTIVE

To summarise available data on the risk factors, complications and the factors associated with complications of lower limb cellulitis in Africa.

METHODS

We did electronic searches on PubMed, EMBASE, Scopus and African Journals Online from 1 January 1986 to 30 October 2017, extracted and summarised data on the risk factors, complications and the factors associated with the complications of lower limb cellulitis from eligible literature.

RESULTS

A total of seven studies were retained for final review after the search and screening processes. Local risk factors of cellulitis reported were: disruption of the skin barrier, neglected wounds, toe-web intertrigo, leg ulcers, use of depigmentation drugs and leg oedema. Obesity was the only reported general risk factor of cellulitis. Five studies reported on the complications of cellulitis which included: abscess formation, necrotising fasciitis, bullae, haemorrhagic lesions, necrosis, phlebitis and amputations. Nicotine addiction, chronic use of non-steroidal anti-inflammatory drugs, delay in the initiation of antibiotic treatment and elevated erythrocyte sedimentation rate were risk factors of complications of lower limb cellulitis identified from three studies.

CONCLUSION

This review highlights the important role of local risk factors in the pathogenesis of lower limb cellulitis in Africa. The association between voluntary skin depigmentation and lower limb cellulitis should alert public health authorities and the general population to the health risks associated with this practice. The identification and improved management of the risk factors of lower limb cellulitis and its complications could go a long way in decreasing the morbidity and health costs incurred by lower limb cellulitis in Africa.

A case report of hemolytic streptococcal gangrene in the danger triangle of the face with thrombocytopenia and hepatitis

Background

Hemolytic streptococcus gangrene is a life threatening invasive bacterial infection. Hemolytic streptococcus gangrene in the danger triangle of the face is too lethal to operate. A case of the confirmed hemolytic streptococcus gangrene in the danger triangle of the face caused by Group A beta-hemolytic streptococcus (GAS) in 20-months old boy is presented to draw attention of clinicians to this uncommon but frequently fatal infection.

Case presentation

Previously healthy 20 months old boy suddenly developed paranasal gangrene on the left side of the danger triangle of the face, followed by rapidly progressive thrombocytopenia and hepatitis. The clinical features, liver function, and hematological and serological parameters resembled to a description of streptococcal toxic shock syndrome (STSS). Aggressive antibiotics, substitutional and supportive therapy were conducted without surgical debridement of facial tissues. Prompt diagnosis and aggressive timely treatment completely cured the disease in 28 days.

Conclusions

The present case report demonstrates prompt diagnosis and timely treatment as a strategy to cure the fatal hemolytic streptococcus gangrene located in too risky body part to operate.

Cutaneous infection and bactaeremia caused by Erwinia billingiae: a case report

Cellulitis and erysipelas are common skin infections usually caused by Staphylococcus aureus and streptococci. Gram-negative rods are rarely implicated. We report here a case of dermohypodermitis and bactaeremia caused by Erwinia billingiae, a Gram-negative bacteria usually pathogenic and epiphytic to pome fruit tree.

Atypical presentation of livedo racemosa in a factor V Leiden heterozygous positive patient with Pseudomonas aeruginosa urosepsis

Impairment of the protein C pathway, detectable by reduced plasma levels of activated protein C (APC), are risk factors for venous thrombosis. Activated protein C maintains clotting homeostasis by regulation of pro-coagulant factors Va and VIIIa. Both infection and the factor V Leiden mutation reduce the formation of APC from protein C in the blood. With low levels of APC, excess factors Va and VIIIa exist, increasing the risk of thrombus formation. Livedo racemosa is characterised by a striking, violaceous branch-like pattering of the skin. It is similar to livedo reticularis, but with a different morphology and histopathology. In this case report we present the first case of livedo racemosa, in an 89-year-old factor V Leiden-positive patient with a Pseudomonas aeruginosa urinary tract infection. The cutaneous biopsies demonstrated vasculopathy with intraluminal thrombi in subcutaneous vessels with no evidence of inflammatory vasculitis.

Necrotising Soft Tissue Infections: The Effect of Hyperbaric Oxygen on Mortality

In a single-centre, retrospective, case-controlled study of patients attending the Alfred Hospital in Prahran, Victoria, we assessed the effect of hyperbaric oxygen therapy (HBOT) in reducing mortality or morbidity in patients with necrotising fasciitis (NF) over a 13-year period from 2002 to 2014. A total of three hundred and forty-one patients with NF were included in the study, of whom 275 received HBOT and 66 did not. The most commonly involved sites were the perineum (33.7%), lower limb (29.9%) and trunk (18.2%). The commonest predisposing factor was diabetes mellitus (34.8%). Polymicrobial NF (type 1 NF) occurred in 50.7% and Group A streptococcal fasciitis (type 2 NF) occurred in 25.8% of patients. Mortality was 14.4% overall, 12% in those treated with, and 24.3% in those not treated with, HBOT. ICU support was required in 248 (72.7%) patients. Independent factors impacting on mortality included HBOT (odds ratio [OR] 0.42 [0.22 to 0.83], P=0.01), increased age (OR 1.06 [1.03 to 1.08], P=0.001) and immunosuppression (OR 2.6 [1.23 to 5.51], P=0.01). Mortality was linked to illness severity at presentation, however when adjusted for severity score and need for intensive care management, HBOT was associated with significant reduction in mortality.

[Risk factors associated with leg erysipelas (cellulitis) in sub-Saharan Africa: A multicentre case-control study]

BACKGROUND

Acute bacterial cellulitis of the leg (erysipelas) is a common problem involving considerable morbidity in dermatology practice in Africa. Previous studies conducted in Europe and North Africa have highlighted lymphoedema and toe-web intertrigo as independent factors associated with leg erysipelas. The aim of this case-control study was to identify risk factors associated with leg erysipelas in sub-Saharan Africa, within a different socio-economic and culture context.

PATIENTS AND METHODS

We conducted a prospective case-control study in hospital dermatology departments in 8 sub-Saharan African countries over a 12-month period (October 2013 to September 2014). Each case of acute leg cellulitis was matched with 2 controls for age (±5 years) and sex. We analysed the general and local factors.

RESULTS

During the study period, 364 cases (223 female, 141 male) were matched with 728 controls. The mean age was 42.15±15.15 years for patients and 42.11±36 years for controls. Multivariate analysis showed the following to be independent risk factors associated with leg erysipelas in our study: obesity (odds ratio [OR]=2.82 ; 95% confidence interval: 2.11-3.76), lymphoedema (OR=3.87, 95%CI: 2.17-6.89), voluntary cosmetic depigmentation (OR=4.29, 95%CI: 2.35-7.83), neglected traumatic wound (OR=37.2, 95%CI: 24.9-57.72) and toe-web intertrigo (OR=37.86, 95%CI: 22.27-64.5).

CONCLUSION

The results of this study confirms the major role of local risk factors (toe-web intertrigo, lymphoedema) previously identified in other geographical settings. However, the originality of our study consists of the identification of voluntary cosmetic depigmentation as a risk factor for leg erysipelas in sub-Saharan Africa.

Predictors of failure of empiric outpatient antibiotic therapy in emergency department patients with uncomplicated cellulitis

BACKGROUND

Despite several expert panel recommendations and cellulitis treatment guidelines, there are currently no clinical decision rules to assist clinicians in deciding which emergency department (ED) patients should be treated with oral antibiotics and which patients require intravenous (IV) therapy at first presentation of cellulitis amenable to outpatient treatment.

OBJECTIVES

The objective was to determine risk factors associated with adult patients presenting to the ED with cellulitis who fail initial antibiotic therapy as outpatients and require a change of antibiotics or admission to hospital.

METHODS

This was a prospective cohort study of patients 18 years of age or older presenting with cellulitis to one of two tertiary care EDs (combined annual census 140,000). Patients were excluded if they had been treated with antibiotics for the cellulitis before presenting to the ED, if they were admitted to the hospital, or if they had an abscess only. Trained research personnel administered a questionnaire at the initial ED visit with telephone follow-up 2 weeks later. Multivariable logistic regression models determined predictor variables independently associated with treatment failure (failed initial antibiotic therapy and required a change of antibiotics or admission to hospital).

RESULTS

A total of 598 patients were enrolled, 52 were excluded, and 49 were lost to follow-up. The mean (±standard deviation [SD]) age was 53.1 (±18.4) years and 56.4% were male. A total of 185 patients (37.2%) were given oral antibiotics, 231 (46.5%) were given IV antibiotics, and 81 patients (16.3%) received both oral and IV antibiotics in the ED. A total of 102 (20.5%, 95% confidence [CI] = 17.2% to 24.2%) patients had treatment failures. Fever (temperature > 38°C) at triage (odds ratio [OR] = 4.3, 95% CI = 1.6 to 11.7), chronic leg ulcers (OR = 2.5, 95% CI = 1.1 to 5.2), chronic edema or lymphedema (OR = 2.5, 95% CI = 1.5 to 4.2), prior cellulitis in the same area (OR = 2.1, 95% CI = 1.3 to 3.5), and cellulitis at a wound site (OR = 1.9, 95% CI = 1.2 to 3.0) were independently associated with treatment failure.

CONCLUSIONS

These risk factors should be considered when initiating empiric antibiotic therapy for ED patients with cellulitis amenable to outpatient treatment.

Is Community-Acquired Methicillin-Resistant Staphylococcus aureus Coverage Needed for Cellulitis?

Methicillin-resistant Staphylococcus aureus (MRSA) has become the dominant strain of Staphylococcus aureus in many communities of the United States. As a result, many clinicians are now empirically covering for this pathogen in the treatment of various skin and soft-tissue infections. Should this practice apply to cellulitis? In order to answer this question, we defined cellulitis and reviewed the pathogenesis, microbiology, and current studies of inpatient and outpatient antimicrobial therapy. The current evidence suggests empirical MRSA coverage for community-acquired cellulitis may not be necessary in non-purulent (non-suppurative) forms of this infection. Most cases are non-purulent and not amenable to culture although antibody studies indicate streptococci are the most common etiologic agents. Current studies of antimicrobial therapy tend to agree with this finding. Empirical beta-lactam therapy directed primarily at streptococci appears sufficient for non-purulent cellulitis regardless of the prevalence of MRSA in the community.

Uncovering common bacterial skin infections

The four most common bacterial skin infections are impetigo, erysipelas, cellulitis, and folliculitis. This article summarizes current information about the etiology, clinical presentation, diagnosis, prevention, treatment, and implications for primary care practice needed to effectively diagnose and treat common bacterial skin infections.

The risk of cellulitis in cirrhotic patients: a nationwide population-based study in taiwan

Background/Aims

Cellulitis is a common infectious disease. However, the risk of cellulitis in cirrhotic patients is not well established, and whether liver cirrhosis is a risk factor for cellulitis remains unknown. This study evaluated the relationship between cellulitis and liver cirrhosis.

Methods

The National Health Insurance Database, which was derived from the Taiwan National Health Insurance program, was used to identify patients. The study group consisted of 39,966 patients with liver cirrhosis, and the comparison group consisted of 39,701 randomly selected age- and sex-matched patients.

Results

During the 3-year follow-up period, 2,674 (6.7%) patients with liver cirrhosis developed cellulitis, and 1,587 (4.0%) patients without liver cirrhosis developed cellulitis (p<0.001). Following a Cox's regression analysis adjusted for age, sex, and underlying medical disorders, the cirrhotic patients demonstrated a greater risk for the occurrence of cellulitis than the non-cirrhotic patients during the 3-year period (hazard ratio [HR], 1.66; 95% confidence interval [CI], 1.55 to 1.77; p<0.001). Additionally, cirrhotic patients with complications also had a greater risk for the occurrence of cellulitis than those patients without complications (HR, 1.23; 95% CI, 1.14 to 1.33; p<0.001).

Conclusions

We conclude that cirrhotic patients have a greater risk of cellulitis than non-cirrhotic patients.

Antibiotic overuse and resistance in dermatology

Antibiotics have a significant role in dermatology, treating a wide range of diseases, including acne, rosacea, inflammatory skin conditions and skin structure infections, such as cellulitis, folliculitis, carbuncles, and furuncles. Because of their consistent use, utility, and availability, antibiotics are susceptible to overuse within the medical practice, and, specific to this discussion, in the dermatologic setting. The issue of continuously increasing risk of antibiotic resistance remains an important concern to the dermatologist. The scope of this review will be to provide an overview of the common antibiotics used in the dermatologic setting with an emphasis on identifying areas of overuse, reported bacterial resistance, and discussion of clinical management aimed at decreasing antibiotic resistance.

Diagnosis and management of skin and soft-tissue infections (SSTI): a literature review and consensus statement on behalf of the Italian Society of Infectious Diseases and International Society of Chemotherapy

Skin and soft-tissue infections (SSTIs) are among the most common bacterial infections, posing considerable diagnostic and therapeutic challenges and resulting in significant morbidity and mortality among patients as well as increased healthcare costs. eight members of the SSTI working group of the Italian Society of infectious Diseases prepared a draft of the statements, grading the quality of each piece of evidence after a careful review of the current literature using MEDLINE database and their own clinical experience. Statements were graded for their strength and quality using a system based on the one adopted by the Infectious Diseases Society of America (IDSA). The manuscript was successively reviewed by seven members of the SSTI working group of the international Society of Chemotherapy, and ultimately re-formulated by all e xperts. the microbiological and clinical aspects together with diagnostic features were considered for uncomplicated and complicated SSTIs. Antimicrobial therapy was considered as well -both empirical and targeted to methicillin-resistant Staphylococcus aureus (MRSA) and/or other main pathogens.

[Survey of general practitioners management of erysipelas]

PURPOSE

A few studies only have focused on ambulatory management of erysipelas.

METHODS

To assess the diagnostic and therapeutic management of erysipelas by general practitioners, and their adherence to the French Society of Infectious Diseases and Dermatology joint 2000 recommendations, we surveyed 114 general practitioners during a 1 year period (from May 1st, 2005 to April 30th, 2006).

RESULTS

Seventy-three general practitioners accepted to participate to the study and 54 cases of erysipelas were reported. Median age of patients was 63 years (range, 18-94) and sex ratio was 0.77. Lower limbs were affected in 83% out of the cases. A skin lesion was reported in 65% of the cases. None of the 15 doppler ultrasonography that were performed identified deep vein thrombosis. Five patients (9%) were initially hospitalized. Only 18% out of the patients were treated by amoxicillin. Most prescribed antimicrobial agents were pristinamycin (31%) and amoxicillin-clavulanate (27%). Median duration of treatment was 10 days. Six patients received an anti-inflammatory drug. Among the 44 patients who had a follow-up visit, 37 patients (84%) recovered and two patients were hospitalized after this follow-up assessment. Two patients experienced a recurrence of erysipelas during the study.

CONCLUSION

As previously reported in the literature, outcome of erysipelas after ambulatory management remains excellent, although recommendations are poorly followed.

Dispersal of Group A streptococcal biofilms by the cysteine protease SpeB leads to increased disease severity in a murine model

Group A Streptococcus (GAS) is a Gram-positive human pathogen best known for causing pharyngeal and mild skin infections. However, in the 1980's there was an increase in severe GAS infections including cellulitis and deeper tissue infections like necrotizing fasciitis. Particularly striking about this elevation in the incidence of severe disease was that those most often affected were previously healthy individuals. Several groups have shown that changes in gene content or regulation, as with proteases, may contribute to severe disease; yet strains harboring these proteases continue to cause mild disease as well. We and others have shown that group A streptococci (MGAS5005) reside within biofilms both in vitro and in vivo. That is to say that the organism colonizes a host surface and forms a 3-dimensional community encased in a protective matrix of extracellular protein, DNA and polysaccharide(s). However, the mechanism of assembly or dispersal of these structures is unclear, as is the relationship of these structures to disease outcome. Recently we reported that allelic replacement of the streptococcal regulator srv resulted in constitutive production of the streptococcal cysteine protease SpeB. We further showed that the constitutive production of SpeB significantly decreased MGAS5005Δsrv biofilm formation in vitro. Here we show that mice infected with MGAS5005Δsrv had significantly larger lesion development than wild-type infected animals. Histopathology, Gram-staining and immunofluorescence link the increased lesion development with lack of disease containment, lack of biofilm formation, and readily detectable levels of SpeB in the tissue. Treatment of MGAS5005Δsrv infected lesions with a chemical inhibitor of SpeB significantly reduced lesion formation and disease spread to wild-type levels. Furthermore, inactivation of speB in the MGAS5005Δsrv background reduced lesion formation to wild-type levels. Taken together, these data suggest a mechanism by which GAS disease may transition from mild to severe through the Srv mediated dispersal of GAS biofilms.

The prognostic values of soft tissue sonography for adult cellulitis without pus or abscess formation

Abstract The current practice for cellulitis in diagnosis and treatment is mainly based on subjective clinical judgement without validated objective guidance. For patients with non-purulent cellulitis needing intravenous antibiotic treatment in hospital, we found soft tissue sonography performed around 4 days after initiation of antibiotics might have prognostic values. The patients with soft tissue sonographic pattern of subcutaneous thickening alone had shorter duration of antibiotic treatment and higher rate of early treatment response to antibiotics than those with the pattern of cobblestone appearance. Larger-scale research may be warranted to validate the prognostic roles of sonography in cellulitis management.

Antibacterial agents in the elderly

Older patients disproportionately suffer the burden of infection in the community and in health care facilities. The rational approach to antimicrobial therapy for older patients with infection requires an appreciation and understanding of the complex immunologic, epidemiologic, pharmacologic, and microbiologic factors that influence the manifestations and consequences of infection in this group. Specific recommendations for common infectious syndromes must take into account the unique needs of older patients and should be tailored for each individual case.

The accurate diagnosis and treatment of lipodermatosclerosis

Patients attending hospital expect to receive effective evidence-based treatment that improves health and minimises the risk of harm. Clinicians working in acute hospitals are often under pressured to treat people quickly and in such circumstances, some conditions can be misdiagnosed and inappropriately treated. This article uses a case study approach to illustrate the important differences in clinical presentation and treatment of acute and chronic lipodermatosclerosis and cellulitis. It also highlights the importance of clinicians receiving ongoing education so that they can improve their knowledge and provide appropriate care for older people. The article also recommends that national guidelines are developed to enable clinicians to differentiate between infective disorders such as cellulitis and venous disorders so that patients receive prompt effective evidence-based treatment.

Biofilms and chronic wound inflammation

In contrast to the commonly accepted hypothesis of host-centred pathology, it is possible that surface bacteria, not host dysfunction, cause the chronicity and perpetual inflammation associated with chronic non-healing wounds.