Clinical immunology review series: an approach to the patient with recurrent infections in childhood

Recurrent or persistent infection is the major manifestation of primary immunodeficiency, which also results in atypical infection with opportunistic organisms. Young children are also vulnerable to infection and recurrent infection is common. While most children with recurrent infection have a normal immunity, it is important to recognize the child with an underlying primary immunodeficiency and investigate and treat appropriately and yet not over investigate normal children. Prompt, accurate diagnosis directs the most appropriate treatment, and early and judicious use of prophylactic antibiotics and replacement immunoglobulin can prevent significant end organ damage and improve long-term outlook and quality of life. This paper describes important presenting features of primary immunodeficiency and indicates when further investigation is warranted.     

Expert Review of Clinical Immunology : a breakthrough in the future

Common variable immunodeficiency (CVID) is a heterogeneous group of disorders, characterized by decreased serum levels of immunoglobulins and abnormal antibody response to protein and/or polysaccharide antigens, leading to recurrent respiratory and gastrointestinal infections, autoimmunity and malignancies. Meanwhile, several monogenic defects with CVID-like phenotype have been identified during the last decade. There is a need to reach international consensus by modifying criteria for CVID, considering various areas of uncertainty in the field.     

Distribution, Infections, Treatments and Molecular Analysis in a Large Cohort of Patients with Primary Immunodeficiency Diseases (PIDs) in Taiwan

One hundred and twenty-four patients (from 120 families) diagnosed as primary immunodeficiency diseases were enrolled from five tertiary medical centers. The distribution by an update eight categories showed 45 patients (13 females/32 males; 36.3%) with “predominant antibody deficiencies,” 27 patients (6/21; 21.8%) with “T- and B-cell immunodeficiency,” 25 patients (9/16; 20.2%) with “congenital defects of phagocyte,” 25 patients (4/21; 20.2%) with “other well-defined immunodeficiency syndromes,” one boy (0.8%) with “disease in immune deregulation” (Chediak-Higashi syndrome) and another with “complement 3 deficiency.” None had “defects in innate immunity” or “auto inflammatory disorders.” Pseudomonas and Salmonella spp. were the two most identified microorganisms in septicemia (39.7%; 27/68 episodes). Twenty-three patients (18.5%) had mortality. Stem cell transplantation succeeded in 7 of 12 patients. In addition to nine patients with DiGerge syndrome recognized by FISH, direct sequencing identified 12 unique mutations from 20 families, reflecting distinct Taiwan geography, although a selection bias may exist.     

Clinical Characteristics and Treatment Outcomes of Patients with Hepatitis C Virus and Human Immunodeficiency Virus Coinfection: Experience at a Single Center in Korea

BackgroundBecause of the very low incidence of human immunodeficiency virus (HIV) coinfection in Korea, data on hepatitis C virus (HCV)/HIV coinfection are limited. This study aimed to investigate the clinical characteristics and treatment outcomes of patients with HCV/HIV coinfection in Korea.MethodsWe performed a retrospective cohort study of all HCV-monoinfected and HCV/HIV-coinfected patients treated with antivirals at National Medical Center in Seoul, Korea, between January 2009 and March 2020.ResultsWe enrolled 220 HCV-monoinfected and 23 HCV/HIV-coinfected patients treated with antivirals. The HCV/HIV-coinfected patients were younger (HCV vs. HCV/HIV: 57.3 ± 11.3 vs. 40.7 ± 10.1 years, P < 0.001) and had a higher proportion of men (HCV vs. HCV/HIV: 54.5% [n = 120] vs. 91.3% [n = 21], P < 0.001) than the HCV-monoinfected patients. Genotype 1b and 2 were most common in both HCV monoinfection and HCV/HIV coinfection groups. HCV-monoinfected patients had a higher incidence of genotype 1b and 2 than HCV/HIV-coinfected patients (HCV vs. HCV/HIV: 95.4% [n = 210] vs. 73.9% [n = 17], P < 0.001), while the HCV/HIV-coinfected patients had genotype 1a (HCV vs. HCV/HIV: 1.8% [n = 4] vs. 21.7% [n = 5], P < 0.001). The fibrosis-4 index was significantly lower in the HCV/HIV-coinfected patients than in the HCV-monoinfected patients (HCV vs. HCV/HIV: 3.81 ± 3.38 vs. 1.66 ± 1.10, P < 0.001). Among the direct-acting antivirals (DAA)-treated patients, the sustained viral response (SVR) rate did not differ significantly between both groups (HCV vs. HCV/HIV: 94.9% [93/99] vs. 90.9% [10/11], P = 0.480).ConclusionIn Korea, the HCV/HIV-coinfected patients who received antiviral treatment were younger, had higher proportion of men and incidence of genotype 1a, and had less advanced fibrosis than the HCV-monoinfected patients. In actual clinical settings, HCV/HIV-coinfected patients show excellent SVR to DAA treatment, similar to HCV-monoinfected patients.     

Comparative Evaluation of MicroScan Walkaway 96 Plus ID/AST System and Mikrolatest Broth Microdilution Kit in Assessing In vitro Colistin Susceptibility of Carbapenem-Resistant Clinical Gram-negative Bacterial Isolates: Experience from a Tertiary Care Teaching Hospital in Rishikesh,Uttarakhand

Context: As reports on colistin resistance are slowly emerging from different parts of the world, it is imperative that the clinical microbiology laboratories should generate accurate in vitro colistin susceptibility results. Aim: The aim is to generate preliminary data on the diagnostic utility of MicroScan WalkAway 96 Plus Identification ID/Antimicrobial susceptibility testing AST system in determining in vitro colistin susceptibility of carbapenem-resistant clinical Gram-negative bacterial isolates. Settings and Design: A pilot study was conducted in a tertiary care teaching hospital located in Rishikesh, Uttarakhand, between May and June 2019. Materials and Methods: Thirty-four carbapenem-resistant Escherichia coli, Pseudomonas aeruginosa and Acinetobacter spp. isolated from various non-repetitive clinical samples during the study period, were subjected to antibiotic susceptibility testing using MicroScan ID/AST system. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry was used to confirm identity of these isolates. Additional colistin susceptibility testing of all test isolates was performed using Mikrolatest minimum inhibitory concentration antibiotic susceptibility testing kit (reference method), which is based on broth micro dilution (BMD) principle. Statistical Analysis Used: Fisher’s exact test. Results: 11.8% (4/34) of the test isolates (100% [2/2] Acinetobacter junii, 10% [1/10] E. coli and 14.3% [1/7] P. aeruginosa respectively) exhibited in vitro colistin resistance by BMD method. Categorical agreement between MicroScan ID/AST system and Mikrolatest kit w. r. t in vitro colistin susceptibility test results was as follows: 71.4% (Acinetobacter baumannii), 85.7% (P. aeruginosa) and 100% (A. junii, A. johnsonii, E. coli and Klebsiella pneumoniae), respectively. Two major errors (MEs) for A. baumannii and one very ME for P. aeruginosa respectively were observed. Conclusions: Data generated by this study will be of help to the clinicians who are often faced with the dilemma of treating multi drug resistant infections with limited treatment options.