Successful intravenous immunoglobulin therapy for recurrent pneumococcal otitis media in young children

Genomic and panproteomic analysis of the development of infant immune responses to antigenically-diverse pneumococci

Streptococcus pneumoniae (pneumococcus) is a nasopharyngeal commensal and respiratory pathogen. This study characterises the immunoglobulin G (IgG) repertoire recognising pneumococci from birth to 24 months old (mo) in a prospectively-sampled cohort of 63 children using a panproteome array. IgG levels are highest at birth, due to transplacental transmission of maternal antibodies. The subsequent emergence of responses to individual antigens exhibit distinct kinetics across the cohort. Stable differences in the strength of individuals' responses, correlating with maternal IgG concentrations, are established by 6 mo. By 12 mo, children develop unique antibody profiles that are boosted by re-exposure. However, some proteins only stimulate substantial responses in adults. Integrating genomic data on nasopharyngeal colonisation demonstrates rare pneumococcal antigens can elicit strong IgG levels post-exposure. Quantifying such responses to the diverse core loci (DCL) proteins is complicated by cross-immunity between variants. In particular, the conserved N terminus of DCL protein zinc metalloprotease B provokes the strongest early IgG responses. DCL proteins' ability to inhibit mucosal immunity likely explains continued pneumococcal carriage despite hosts' polyvalent antibody repertoire. Yet higher IgG levels are associated with reduced incidence, and severity, of pneumonia, demonstrating the importance of the heterogeneity in response strength and kinetics across antigens and individuals.

Successful discontinuation of immunoglobulin G replacement at age 10 in a patient with immunoglobulin G2 deficiency

CONTEXT

Immunoglobulin G2 deficiency that persists beyond the age of 6 years is likely to be permanent.

CASE REPORT

We report on a young Japanese female, diagnosed as having immunoglobulin G2 deficiency and low anti-pneumococcal immunoglobulin G2 antibody levels when 3 years old, with a subsequent medical history of frequent respiratory infections and asthma. Monthly intravenous immunoglobulin replacement therapy was started at 4 years of age. After 8 years of age, an anti-pneumococcal immunoglobulin G2 trough level could be maintained with administration intervals longer than 6 weeks, and after 9 years and 10 months of age, therapy was discontinued. The frequency of hospital admissions was reduced by the introduction of the replacement therapy (from 8.4 times/year before the introduction to 1.1 times/year during the therapy). The patient was also able to discontinue daily medications for asthma, and serum immunoglobulin G2 was maintained at a normal level even after the cessation of replacement therapy.

CONCLUSION

Termination of immunoglobulin replacement therapy in a patient with a symptomatic immunoglobulin G2 deficiency is possible, even for a child older than 6 years.

Immunotherapies in infectious diseases

The development of an infection involves interplay between the host's immune system and the virulence of the infecting microorganism. The traditional treatment of an infection involves antimicrobial chemotherapy to kill the organism. The use of immunotherapies in infections includes treatment options that modulate the immune response and can lead to control of infections. These therapies are expected to become more important therapeutic options with the increase in infections due to multidrug-resistant organisms and the increasing number of immunocompromised patients.

Effects of Japanese herbal medicine, Juzen-taiho-to, in otitis-prone children--a preliminary study

CONCLUSION

Juzen-taiho-to (JTT, TJ-48), a Japanese herbal medicine that improves immune function, was found to be effective in otitis-prone in children.

OBJECTIVE

To evaluate the efficacy of JTT against intractable and recurrent infections in immature immune systems, we administered JTT to otitis-prone infants and investigated clinical changes before and during JTT administration.

SUBJECTS AND METHODS

Twenty-four otitis-prone infants were administered JTT at 0.10-0.14 g/kg/day twice a day for 3 months. We compared clinical course, such as frequency of acute otitis media (AOM), duration of fever and antibiotics administration, and hospital visits for the periods before and during JTT administration.

RESULTS

Medication compliance rate was 87.5%, and administration of JTT led to remission in 95.2% patients. No apparent side effects were observed. The frequency of AOM decreased significantly (Wilcoxon signed rank test, p=0.000) with JTT. The duration of fever (p=0.000) and administration of antibiotics (p=0.001), as well as the number of hospital visits (p=0.001) and emergent hospital visits (p=0.000) showed significant decreases after JTT administration. After the end of the JTT period, 14 of 21 (66.7%) patients started to take it again, as they experienced purulent otitis media and/or other infections after discontinuation. The frequency of AOM increased significantly after stopping JTT (p=0.004) and decreased again with JTT resumption (p=0.005).

Antibody-based therapies as anti-infective agents

Antibody-based therapies are effective against a wide variety of pathogens. Historically, antibody-based therapies were largely abandoned with the advent of antimicrobial chemotherapy, due to the toxicity associated with the administration of heterologous immune sera. As a class, antibody-based therapies have significant advantages and disadvantages relative to conventional antimicrobial chemotherapy. Advantages include versatility, specificity, and antimicrobial activities not available in antibiotic drugs, such as toxin and viral neutralisation, opsonisation, complement activation and the enhancement of host immune function. Disadvantages include expense, the necessity for early and accurate diagnosis prior to use, and the complex logistics necessary for therapeutic use. Advances in antibody technology have minimised some of the disadvantages associated with antibody therapy. In recent years, the therapy of infectious diseases has been complicated by the emergence of new pathogens, the spread of antibiotic-resistant strains and the relative inefficacy of antimicrobial chemotherapy in immunocompromised hosts. This has led to renewed interest in the utilisation of antibody-based therapies as anti-infectives. Many opportunities for developing antibody-based drugs now exist in areas where the available antimicrobial therapies are inadequate.

Therapy for otitis-prone children in Tenshi hospital

With the recent emergence and increases of multiple-drugs-resistant Streptococcus pneumoniae, we have been seeing an increasing number of infants with intractable recurrent otitis media which is resistant to the general conservative out-patient treatments such as oral administration of medicines or tympanotomy. In this study, we investigated the inflammation-causing bacteria in the infants with otitis media which were treated in our hospital from January to December in 1997, and in six serious cases among them, we measured IgG subclass and specific IgG2 antibody to S. pneumoniae to examine them. As a result, S. pneumoniae was found to be the cause in 45% of the cases of initial development of otitis media, and in 88% of them the S. pneumoniae was penicillin-resistant. The level of specific IgG2 antibody to S. pneumoniae was low in all the cases, whereas IgG2 subclass was deficient only in one out of the six cases; from these findings, the selectively low level of immune status was thought to be the cause of the recurrences of otitis media. In two cases, clinical condition was markedly improved by immunoglobulin substitute therapy, which demonstrates that immunoglobulin is effective for the intractable recurrent otitis media in infants.

Passive immunity in prevention and treatment of infectious diseases

Antibodies have been used for over a century in the prevention and treatment of infectious disease. They are used most commonly for the prevention of measles, hepatitis A, hepatitis B, tetanus, varicella, rabies, and vaccinia. Although their use in the treatment of bacterial infection has largely been supplanted by antibiotics, antibodies remain a critical component of the treatment of diptheria, tetanus, and botulism. High-dose intravenous immunoglobulin can be used to treat certain viral infections in immunocompromised patients (e.g., cytomegalovirus, parvovirus B19, and enterovirus infections). Antibodies may also be of value in toxic shock syndrome, Ebola virus, and refractory staphylococcal infections. Palivizumab, the first monoclonal antibody licensed (in 1998) for an infectious disease, can prevent respiratory syncytial virus infection in high-risk infants. The development and use of additional monoclonal antibodies to key epitopes of microbial pathogens may further define protective humoral responses and lead to new approaches for the prevention and treatment of infectious diseases.

Passive immunity in prevention and treatment of infectious diseases

Antibodies have been used for over a century in the prevention and treatment of infectious disease. They are used most commonly for the prevention of measles, hepatitis A, hepatitis B, tetanus, varicella, rabies, and vaccinia. Although their use in the treatment of bacterial infection has largely been supplanted by antibiotics, antibodies remain a critical component of the treatment of diptheria, tetanus, and botulism. High-dose intravenous immunoglobulin can be used to treat certain viral infections in immunocompromised patients (e.g., cytomegalovirus, parvovirus B19, and enterovirus infections). Antibodies may also be of value in toxic shock syndrome, Ebola virus, and refractory staphylococcal infections. Palivizumab, the first monoclonal antibody licensed (in 1998) for an infectious disease, can prevent respiratory syncytial virus infection in high-risk infants. The development and use of additional monoclonal antibodies to key epitopes of microbial pathogens may further define protective humoral responses and lead to new approaches for the prevention and treatment of infectious diseases.

Salivary anti-capsular antibodies in infants and children immunised with Streptococcus pneumoniae capsular polysaccharides conjugated to diphtheria or tetanus toxoid

Saliva samples of infants and children immunised with pneumococcal vaccines were analysed for anti-polysaccharide (PS) antibodies against the Streptococcus pneumoniae (Pnc) vaccine serotypes 6B, 14, 19F, and 23F. The children received Pnc conjugate vaccine (1, 3, or 10 micrograms of PSs conjugated to diphtheria or tetanus toxoid) or placebo at 2, 4, and 6 months. At 7 months of age salivary PS antibodies were detected rarely. All children received Pnc conjugate or PS vaccine at 14 months of age. At 15 months, both IgA and IgG anti-Pnc PS were found, anti-19F and anti-14 antibodies occurring most frequently and in the highest concentrations. IgA was in the secretory form and predominantly IgA1. A negative dose dependency was observed in IgA anti-19F response. In general, no clear differences in salivary antibody responses were found between the children primed with conjugate vaccine in infancy and those who received their first Pnc vaccine at 14 months of age, suggesting that priming with Pnc conjugate vaccines does not lead to remarkable mucosal memory responses.

A prospective, double-blind, placebo-controlled trial of i.v. immunoglobulin and trimethoprim-sulfamethoxazole in children with recurrent respiratory tract infections

In a prospective, double-blind, placebo-controlled study of iv immunoglobulin (IVIG) and trimethoprim-sulfamethoxazole (TMS), 130 children less than 8 years of age were referred for recurrent bacterial respiratory tract infections, as judged by the referring physician. Of the 130 children referred, only 24 continued to have bacterial respiratory infections over a 4-month observation period. They were randomized and 23/24 treated for 4 months during the winter-spring season. The 7 children given placebo for both IVG adn TMS continued to have bacterial respiratory infections, while 14 of 16 children given active therapy with either IVIG or TMS became infection-free (p=0.002). No relation to IgG subclass level or between the two modalities of treatment was found. We concluded that most infection-prone children suffer from viral infections and are given antibiotics unnecessarily. Of the small group of children that have documented, repeated bacterial infections, prophylactic therapy with either IVIG or TMS can substantially diminish the number of infections.