Colonization of Staphylococcus aureus and sensitivity to antibiotics in children with atopic dermatitis

PURPOSE: Staphylococcus aureus colonization exacerbates atopic dermatitis. Local or systemic antibiotics can increase difficulty in controlling skin colonization and the possibility of methicillin-resistant S. aureus (MRSA). Choosing appropriate antibiotics has become more challenging. We investigated the frequency of S. aureus and MRSA colonization and susceptibility to antimicrobial agents. METHODS: We collected and cultivated the skin colonization samples of atopic dermatitis children less than 20 years old from June 2006 to May 2016, and tested the antibiotic sensitivity. We also checked the severity of atopic dermatitis by SCORing Atopic Dermatitis (SCORAD) index and analyzed. RESULTS: Out of 2,355 subjects, 1,935 (82.2%) had S. aureus and 762 (39.4%) had MRSA. The frequency of MRSA increased from 13.3% in 2006 to 26.6% in 2007, 18.4% in 2008, 27.1% in 2009, 38.3% in 2010, 42.6% in 2011, 42.4% in 2012, 48.3% in 2013, 44.5% in 2014, 38.1% in 2015, and 37.5% in 2016. Mupirocin resistance started with 0% in 2009, and gradually increased annually to 13.7% in 2010, 14.7% in 2011, 25.4% in 2012, 35.2% in 2013, 34.9% in 2014, 39.8% in 2015, and 35.6% in 2016. The mupirocin resistant group has a higher SCORAD index than the other groups (P<0.05). CONCLUSION: MRSA frequency and mupirocin resistance tended to increase annually. We should choose the methods of managing bacterial colonization in atopic dermatitis carefully in order to prevent antibiotic resistance.

The association between Staphylococcus aureus colonization and food sensitization in children with atopic dermatitis

PURPOSE: Atopic dermatitis is often accompanied by food allergies which occur through skin barrier defects. Especially Staphylococcus aureus colonization can exacerbate skin barrier defects that cause sensitization and increase specific IgE (sIgE) to food. We investigated the association between skin colonization and food sIgE changes in children with atopic dermatitis. METHODS: Atopic dermatitis was diagnosed by a pediatric allergist in patients between 3 months and 3 years of age. Total IgE and sIgE to egg white, cow's milk, wheat, and peanuts were taken. Eosinophil count and eosinophil cationic protein were also taken. Comparisons were done between the groups with and without S. aureus colonization. RESULTS: It was found that 50.3% of the 294 enrolled patients had S. aureus colonization on lesional skin. Statistically significant sensitization to wheat and peanut were increased with S. aureus colonization. Statistically significant increases in sIgE (above cutoff level) were also found in egg white, milk, wheat and peanut. Higher S. aureus colony counts also increased sIgE of all foods. Methicillin-resistant S. aureus showed no statistical difference compared to methicillin-susceptible S. aureus in severity and sIgE levels. CONCLUSION: S. aureus colonization increases the risk of food sensitization in children with atopic dermatitis.

Molecular Characterization of Community-Associated Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus Isolates from Children with Skin Infections in Busan, Korea

The prevalence and molecular characteristics of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) and methicillin-susceptible S. aureus (CA-MSSA) from children with skin infection were investigated by staphylocoagulase (SC) typing, multilocus sequence typing (MLST), SCCmec typing and virulent toxins, including Panton-Valentine leucocidin (PVL), and exfoliative toxins (ET). Among 69 cases of CA-S. aureus for a 3 month period from March to June, 2014 at hospital in Busan, 28 (40.6%) were MRSA and 41 (59.4%) were MSSA. Of the 28 CA-MRSA isolates, two major clones were identified as SC type Vb-ST72-SCCmec type IV (53.6%) and SC type l-ST89-SCCmec type II variant (42.8%), and the remaining one (3.6%) was SC type lll-ST8-SCCmec type IV. In CA-MSSA, the prevalent clone was SC type Vb-ST72 (29.3%), followed by SC type Vb-ST188 (21.9%), SC type Va-ST121 (19.5%) and SC type lV-ST30 (9.6%). None was positive for PVL gene, and all of the SC type l-ST89-SCCmec type II variant clones were ETB gene positive. The data suggest that there are significant clonal relatedness with specific SC types, and genetic diversities in both community strains isolated from children with skin infections.

High-dose caspofungin salvage in a very-low-birth-weight infant with refractory candidemia / 소아과

Candidiasis is one of the most common causes of late-onset infection among very-low-birth-weight infants (VLBW) in most neonatal intensive care units and is associated with significant morbidity and mortality. Standard therapy consists of the administration of amphotericin B, amphotericin B complex, and fluconazole. In many cases, candidiasis is not easily eradicated, despite the administration of these drugs. We report our experience of the addition of high-dose caspofungin to the conventional antifungal drugs in a VLBW infant with refractory candidemia.

Immunohistochemical Study on the Expression of Topoisomerase II alpha and Glutathione S-Transferase pi in Acute Myeloid Leukemia / 대한임상병리학회지

BACKGROUND: Topoisomerase II (topo II) is a major target of anthracyclines and epipodophyllotoxins for anticancer treatment. The expression of topo II is low in drug resistant cell lines. High levels of glutathione S-transferase (GST)pi have been associated with emergence of cell lines resistant to alkylating agents or adriamycin. METHODS: By immunostaining with paraffin embedded bone marrow tissues, the expression of topo II alpha and GSTpi was investigated in 51 patients with acute myeloid leukemia (AML), and the relation of topo II alpha and GSTpi expression to treatment response in 29 patients with AML following induction chemotherapy was also evaluated. RESULTS: Topo II positive cells varied from less than 1% to 60% of leukemic cells and 20 (39.2%) were negative for topo II (positive cells<10%). Treatment response following chemotherapy was not related to topo II. 26 (51.0%) were positive for GSTpi. GSTpi expression was related to treatment resistance of the patients following chemotherapy. In the patients who showed both topo II alpha negative and GSTpi positive, the frequency of treatment resistance following chemotherapy was high. CONCLUSIONS: This study suggests that immunostaining of topo II alpha and GSTpi with the bone marrow paraffin sections of AML patients can be useful to predict the treatment response following chemotherapy and that further study including more patients with prospective study may substantiate topo II alpha and GSTpi as multidrug resistant markers.

Synovial Fluid Adenosine Deaminse Activity in the Patients of Rheumatoid Arthritis, Osteoarthritis, Ankylosing Spondylitis, and Gouty Arthritis / 대한류마티스학회지

OBJECTIVE: To investigate whether synovial fluid adenosine deaminase activity is useful in the differential diagnosis of joint swelling and in estimating the disease activity. METHOD: Adenosine deaminase activity was determined in the synovial fluid taken from patients with rheumatoid arthritis (n=21), osteoarthritis (n=ll), ankylosing spondylitis (n=3), and gouty arthritis (n=2). This enzyme activity was compared with the laboratory indices (ESR, CRP) in the blood and the other parameters in the synovial fluid. RESULT: More increased adenosine deaminase activity was found in the synovial fluid taken from patients with rheumatoid arthritis, ankylosing spondylitis, and gouty arthritis, as compared with that of osteoarthritis patients. Synovial fluid ADA activity was significantly corelated with the WBC count in the synovial fluid, but there was no statistical corelation between other synovial parameters and adenosine deaminase activity. CONCLUSION: Adenosine deaminase activity is useful in the differential diagnosis of joint swelling between inflammatory joint disease and osteoarthritis, but not useful in estimating the disease activity.