INHERITABLE DISORDERS OF INTERFERON-12 PATHWAY: DIAGNOSIS AND MANAGEMENT
Khalilzadeh Soheila, Adimi Parisa, Boloursaz Mohammad Reza, Nooshin Baghaie, Khodayari Amir Ali, Mansouri Davood
Department of Pediatrics and Pulmonology, TB and Lung Disease Research Center , NRITLD, Masih Daneshvari Hospital, Shahid Beheshti University, Iran
Address for Correspondence
Masih Daneshvari Hospital, Darabad Ave, Tehran, IR Iran.
Email
soheilak@yahoo.com
Abstract
Background: Disseminated BCG infection is a typical clinical presentation in patients with an inherited disorder of the Interleukin (IL)-12-Interferon (INF)-g axis, as BCG is often the first pathogen to which patients are exposed. BCG sub strains are derived from Mycobacterium bovis. BCG vaccination is routinely carried out in most regions of the world, with up to 95% coverage of children in Iran.

Materials and Methods: Sixteen patients were found with disseminated BCG disease, with the age range between 1 month-14 years. Diagnosis was based on positive culture of M. bovis-BCG variant from blood, sputum, gastric washing, and abscess or biopsy sites. Results of laboratory tests, radiological and CT-scan findings from the site of involvement were assessed and classified.

Results: Out of 16 cases, 63% of the cases (10 patients) were males while 37% (6 patients) were females. Mean age of the patients was 4.75 ± 3.39 years old. The most common site of peripheral lymph node involvement was axillary (78%). Lung and para-aortic lymph adenopathy were the commonest site of central involvement. Six patients (38%) had defects in IL-12-INF-g axis of which three of them had IL-12Rβ₁ deficiency (mutation) and two had IL-12p40 deficiency and one had INF-g R2 deficiency.

Conclusion: Considering the results of this study, it should be emphasized that prior to BCG vaccination, in cases with the family history of BCG-osis, all siblings should be evaluated for immune system disorders.
Keywords
Disseminated BCG, IL-12, Interferon gamma defect, Bacille Calmette-Guerin, Children, Iran, BCGosis
Introduction
Interferon-g is a critical cytokine produced by Non-killer (NK) and T-cells. The differentiation of T-helper cells into Interferon (INF)-g-producing cells is regulated by several cytokines, but principally interleukin-12 (IL-12). IL-12 is produced by antigen-presenting cells (particularly dendritic cells and macrophages) in response to infection. IL-12 not only promotes T-helper cell differentiation, but also induces INF-g production in other cells, such as NK cells. Deletions in germline mutations in five genes involved in the IL-12-INF-g circuit have been found in human patients: IFNGR1, encoding the ligand-binding chain of the INF-g receptor(INF- g r1); IFNGR2, encoding the associated chain of the INF-g receptor (INF-g r2); STAT1, encoding the signal transducer and activator of transcription-1 (STAT1) in the INF receptor signaling pathway; IL12B, encoding the beta 1 subunit shared by the IL-12 and IL-23 receptors (IL-12Rβ₁).(1) Disseminated BCG infection is a typical clinical presentation in patients with an inherited disorder of the IL-12-INF-g axis, as BCG is often the first pathogen to which patients are exposed. BCG substrains are derived from Mycobacterium bovis. BCG vaccination is routinely carried out in most regions of the world, with up to 95% coverage of children in Iran.
BCG prevents severe forms of childhood tuberculosis (TB), including miliary tuberculosis and meningitis in particular; however, in rare patients, BCG vaccination results in disseminated infection involving lymph nodes, lungs, kidney, spleen and other organs. Such infections are referred to as "BCG-osis" and are complications of BCG injection, with high (71%) rates of mortality (2).

BCG-osis invariably indicates the presence of an underlying congenital or acquired immune deficiency, such as severe combined immunodeficiency (SCID), chronic granulomatous disease (CGD) or HIV infection. Patients with these conditions are also vulnerable to various other microbes. Of the remaining patients with BCG-osis, half present MSMD (mendelian susceptibility to mycobacterial disease). About half of the known MSMD patients have been shown to present an inherited defect of the IL-12-INF-g axis, whereas the remaining cases remain asymptomatic. (3)

We report here the cases of BCG-osis with hereditary defects in the IL-12-INF-g axis and describe the clinical, paraclinical and molecular features.
Methods & Materials
In this study, clinical, laboratory, radiological and molecular data were obtained from the medical records of all patients with Disseminated BCG disease admitted in the pediatric ward at National Research Institute of Tuberculosis and Lung disease (NRITLD), a referral center for Tuberculosis and lung disease, located in Tehran capital of Iran, during a 8 year period (1999-2007). Medical history including personal and family history, physical examination data, growth and development chart, site of lymphadenopathy were obtained in all patients. Diagnosis was based on positive culture of M. bovis, BCG variant, from blood, sputum, gastric washing, and abscess or biopsy sites. Results of laboratory tests, radiological and CT-scan findings from the site of involvement were assessed and classified. Induration's of more than 10mm by tuberculin skin test (Mantoux test by intra dermal injection; 0.1 ml of 5 tuberculin units) was taken as positive. Analysis of peripheral blood B lymphocytes (CD19), T lymphocytes (CD3), T cell subpopulations (CD4, CD8), natural killer cells (CD56+, CD16) and also of serum immunoglobulins was done.


The ability of interferon-g to up-regulate the production of TNF-a by monocytes was studied with an in vitro whole-blood assay. The production of TNF-a in response to Escherichia coli lipopolysaccharide (1 μ per milliliter ) was compared with TNF-a production induced by the same concentration of lipopolysaccharide after pretreatment with interferon-g (2μg per milliliter) for two hours. Plasma TNF-a levels were measured with an enzyme-linked immunosorbent assay.
Results
Sixteen patients were found with disseminated BCG disease, with the age range between 1 month-14 years and mean age of 4.75 ± 3.39 years old. Male:Female ratio was 10:6. Clinical and radiological features are depicted in Table 1. Scar of previous BCG vaccination was observed on the right arm of all children. On an average, the onset of symptoms appeared at 5.5 months of age. Considering the growth chart, 50% (8 cases) were below the 10th percentile curve. Abscess at the injection site was reported in all of the cases. In CT scan, abdominal involvement was observed in 10 patients (71.4%). In this group, 100% had para-aortic lymphadenopathy, with retroperitoneal lymphadenopathy in one case. 20% of patients had ascites, splenomegaly and abscess formation were seen in 2 cases. In one case hyper resonance nodules was present in the spleen and in another one hyperechoic mass was detected in liver. Tuberculin skin test was positive in 6(37.5%) children.

8 children (50%) demonstrated hypogammaglobulinemia (IgG < 1000 & IgA <100). Lymphocyte subsets were low in 31 %( 5 cases). Direct smear of gastric washing for AFB were positive in 25 %( 4 cases), culture of gastric lavage was positive in 12.5 %(2 cases), results of PCR sampling on gastric washing for M.bovis were positive in 18.7 % (3 cases). Direct smear and culture for AFB on lymph node sampling were positive in 18.7 %(3 cases). Pathologic findings compatible with chronic mycobacterial granulomatous tissue with necrosis were seen in 63% (10 cases) of lymph node biopsies.

Six patients (38%) had defects in IL-12-INF-g axis of which three of them had IL-12Rβ₁ deficiency (mutation) and two had IL-12p40 deficiency and one had INF-g R2 deficiency. All patients had negative serology for HIV infection.

All patients received the anti TB medication (Isonaizid, Rifampicin and Ethambutol). Meanwhile in five cases due to poor clinical response and progression of the disease, in addition to the above anti TB regimens, Clarithromycin and Ofloxacin were added. Gamma interferon was used in one case. All the patients are alive and are under regular follow-up.

Table 1: Clinical and radiological features of children with BCGosis
Lymphadenopathy 100%
Right axillary adenopathy (69) 31%
Hilar adenopathy 25%
Mediastinal adenopathy 19%
Left axillary adenopathy 13%
Fever 85%
Weight Loss 80%
Splenomegaly 53%
Pneumonia 42%
Pulmonary abscess 7%
Skin involvement 7%
Pulmonary Nodule 7%
Lobar consolidation 4%
Discussion
Immunization of children with Bacillus Calmette-Guerin (BCG), a live attenuated bacterial vaccine derived from Mycobacterium Bovis, is recommended by the World Health Organization in communities with a high prevalence of tuberculosis. (1,2) BCG vaccines are extremely safe in immunocompetent hosts, but possible complications range from local inflammatory reactions (lymphadenitis, abscess and fistula formation) to disseminated diseases (osteomyelitis, bacteremia, meningitis) and death. (3) We found disseminated BCG more common in boys as compared to a study by Deeks et al in Canada during 2005 where the incidence of disseminated BCG disease was slightly higher in girls as compared to boys (4).

In Iran, BCG vaccination is performed immediately after birth. It has been shown in different studies that the complications of BCG vaccination appear within 6 months of birth. (5, 6) In this study mean age for the appearance of the symptoms was 5.5 months. In one case, symptoms appeared at 6 years of age. Most of the clinical signs in our study comprised of fever, weight loss and lymphadenopathy. Also in study by Casanova et al, fever and cachexia were common in the patients. In our study, 78.6% had pulmonary and 71.4% suffered from abdominal involvement. Casanova and his colleagues demonstrated lymph node involvement in 94%; with 69% having pulmonary involvement. (7) Other studies also have demonstrated abdominal involvement in more than 30% and renal involvement in 19% of the cases. In our study, one of the patients (7.1%) had involvement of the urinary system.

BCG vaccine is contraindicated for people with immunodeficiency diseases. Most of children with disseminated disease have immunodeficiency disorders and should not receive the vaccine if their condition is known. However, the vaccine is given in the neonatal period when it is often difficult to elicit a history of or detect immunodeficiency disorders. This is particularly true for conditions such as SCID, CGD, IL-12-INF-g axis, for which no neonatal screening test is routinely performed (8, 9,10)

The records of our review showed that most of patients with disseminated BCG disease had immunodeficiency. Immune defects in the IL-12-INF-g axis were identified in six subjects, also genetic study for INF-g receptor deficiency is in progress. In a study by Farhoudi, et al. one of the 6 cases had INF-g receptor deficiency. (11) In the retrospective review of disseminated BCG disease by Lotte, et al, all the 60 patients took part in that study, had cellular immunodeficiency and 31 of these patients died.(12) Additionally, in study of Talbot et al immunodeficiency was identified in 24 out of 28 subjects.(1)]

Recently, patients with severe infections due to otherwise poorly pathogenic mycobacteria (non-tuberculous mycobacteria or Mycobacterium bovis BCG) or Salmonella species have been identified with IL-12 IFN g receptor deficiency. Many of these patients were unable to produce or respond to interferon gamma. Unusual mycobacterial infections were also reported in several patients with genetic defects in inhibitor of NFkappaB kinase gamma, a key regulatory molecule in the nuclear factor kappaB pathway. (14) The first seven cases of IL-12Rβ₁ deficiency were published in 1998. Eight years later, 89 IL-12Rβ₁-deficient patients have been described, including 62 published cases. IL-12Rβ₁ deficiency is therefore the most frequent known genetic etiology of MSMD. Forty-one mutant alleles have been identified, 29 of which have been published. All mutant alleles are recessive, loss-of-function and cause recessive complete IL-12Rβ₁ deficiency. In this study, we report three patients with BCG-osis with IL-12Rβ₁ deficiency, mycobacterial disease and salmonellosis are the most frequent infectious disease in patients with IL-12Rβ₁ deficiency. Like IL-12p40-deficient patients, about half of all the known IL-12Rβ₁-deficient patients have developed Salmonella infection. Infectious disease occurred before the age of 12 years in symptomatic patients, as in patients with RC-INF-g R1 or INF-g R2 deficiency. However, unlike these patients, the clinical outcome was relatively good, with only 17% deaths, and most patients surviving into adulthood, although our three patients are in childhood period. (15,16)

All known IL-12B mutations are recessive and loss-of-function, resulting in recessive complete IL-12p40 deficiency with a lack of detectable IL-12p40 secretion by the patients' blood cells and EBV-transformed B cells. Our patient with IL-12p40 deficiency presents a novel mutation in IL12B, indicating that IL-12 deficiency is not restricted geographically and that the spectrum of mutations is not as limited as previously thought. The patient suffered chronic infection with a reasonably good outcome. We suggest that the overall prognosis of such cases is good, with broad resistance, low peneterance of the mutation and a favorable outcome regarding of infection.

INF-g R2 deficiency is one of the rarest genetic etiologies of MSMD: only nine children have been identified, including seven children from the six families reported to date. The first patient was reported in 1998. This child and six other patients had recessive complete (RC) INF-g R2 deficiency. Two forms of RC INF-g R2 deficiency were documented. The study of INF-g R2 deficiency has had unexpected genetic implications, beyond the field of MSMD and even that of primary immunodeficiencies. (17, 18)

In one of our patients investigation of the IL-12-INF-g axis by means of a recently developed whole-blood cells in response to BCG plus INF-g sequencing of the INFGR1, INFGR2, and STAT1 genes revealed that the patient was homozygous for a missense mutation in INFGR2 (T168N). The parents were heterozygous for this mutation, which was not found in 100 healthy controls tested. The pathogenic effects of this mutation were shown to be due to the creation of a novel N-glycosylation site in INF-g R2. The receptors were expressed on the cell surface, defining a novel form of INF-g R2 deficiency. These data unambiguously demonstrated the presence of an autosomal recessive, complete INF-g R2 deficiency in this patient. By analogy with other INF-g R2-deficient patients and the larger number of patients with complete INF-g R1 deficiency, this patient probably has a poor prognosis, despite his current clinical remission.

Inherited INF-g R1 deficiency was the first genetic etiology of MSMD to be identified, in 1996.(18) In the last 10 years, 30 different INFGR1 mutations have been identified in 86 patients world-wide. INF-g R1 deficiency is a very severe condition, with an early onset of infection and a poor prognosis.(19) Children are mostly infected by BCG and environmental mycobacteria, notably rapidly growing mycobacteria such in our patient with INF-g R1 deficiency the type of bacilli was mycobacterium rapid growing.(20) The clinical penetrance of INF-g R1 deficiency is complete in childhood, and the mean age at onset of first infection is 3.1 years compared to our patient the onset of symptoms was 2 year old. Most of the affected children died in childhood and only four of the 22 published patients reached the age of 12 years, our case now is 6 years old. Antibiotic treatment does not give full and sustained clinical remission and INF-g has no effect in the absence of a functional receptor. (21)

In various studies, the rate of mortality and morbidity among children with disseminated BCG disease is greater than 70%. (22) Also in Casanova, et al. study the prognosis of BCG infection was poor and mortality rate reported as 43%. In the study of Afshar Paiman, et al. most of their patients died despite aggressive management. (1) However in our study, one of our patients expired due to dissemination of BCG infection.

Treatment of these diseases include: anti bacterial, anti tuberculosis in addition to INF-g in selected cases. More advanced treatment procedures, such as bone marrow transplantation or gene therapy, might improve the prognosis of such patients in the future. (20)
Funding
None
Conflict of Interest
None
References :
  1. Afshar Paiman S, Siadati A, Mamishi S, Tabatabaie P, Khotaee G. Disseminated Mycobacterium bovis Infection after BCG Vaccination. Iran J Allergy Asthma Immunol. 2006 ;5(3):133-7.
  2. Colditz GA, Berkey CS, Mosteller F, et al. The efficacy of bacillus Calmette-Guerin vaccination of newborns and infants in the prevention of tuberculosis: meta-analyses of the published literature. Pediatrics. 1995;96:29 -35.
  3. Wiker HG, Bjune G. Tuberculosis vaccines Tidsskr Nor Laegeforen. 2006 19;126(20):2678-81.
  4. Deeks SL, Clark M, Scheifele DW, Law BJ, Dawar M, Ahmadipour N, Walop W,Ellis CE, King A. Serious adverse events associated with bacille Calmette-Guerin vaccine in Canada. Pediatr Infect Dis J. 2005 ;24(6):538-41.
  5. Abaev IuK. Surgical complications following BCG vaccination Vestn Khir Im I I Grek. 2006;165(2):122-4.
  6. Muto J, Kuroda K, Tajima S. Papular tuberculides post-BCG vaccination: case report and review of the literature in Japan. Clin Exp Dermatol. 2006 ;31(4):611-2.
  7. Casanova JL, Blanche S, Emile JF, Jouanguy E, Lamhamedi S, Altare F, Stephan JL, Bernaudin F, Bordigoni P, Turck D, Lachaux A, Albertini M, Bourrillon A, Dommergues JP, Pocidalo MA, Le Deist F, Gaillard JL, Griscelli C, Fischer A. Idiopathic disseminated bacillus Calmette-Guerin infection: a French national retrospective study.Pediatrics. 1996 ;98(4 Pt 1):774-8.
  8. Culic S, Kuzmic I, Culic V, Martinic R, Kuljis D, Pranic-Kragic A, Karaman K, Jankovic S. Disseminated BCG infection resembling langerhans cell histiocytosis in an infant with severe combined immunodeficiency: a case report.Pediatr Hematol Oncol. 2004 ;21(6):563-72.
  9. Hodsagi M, Uhereczky G, Kiraly L, Pinter E. BCG dissemination in chronic granulomatous disease (CGD).Dev Biol Stand. 1986;58 ( Pt A):339-46.
  10. Doffinger R, Dupuis S, Picard C, Fieschi C, Feinberg J, Barcenas-Morales G,Casanova JL. Inherited disorders of IL-12- and IFNgamma-mediated immunity: a moleculargenetics update.Mol Immunol. 2002 ;38(12-13):903-9.
  11. Movahedi M, Aghamohammadi A, Rezaei N, Shahnavaz N, Jandaghi AB, Farhoudi A,Pourpak Z, Moin M, Gharagozlou M, Mansouri D. Chronic granulomatous disease: a clinical survey of 41 patients from the Iranian primary immunodeficiency registry.Int Arch Allergy Immunol. 2004 ;134(3):253-9.
  12. Lotte A, Wasz-Hockert O, Poisson N, et al. BCG complications: estimates of the risks among vaccinated subjects and statistical analysis of their main characteristics. Adv Tuberc Res. 1984;21:107-193.
  13. Talbot EA, Perkins MD, Silva SFM, et al. Disseminated bacilli Calmette-Gue´rin disease after vaccination: case report and review. Clin Infect Dis. 1997;24:1139 -1146.
  14. Mansouri D, Adimi P, Mirsaeidi M, Mansouri N, Khalilzadeh S et,al. Inherited disorders of the IL-12-INF-g axis in patients with disseminated BCG infection. Eur J Pediatr 2005 164: 753-757.
  15. Hunter CA. New IL-12-family members: IL-23 and IL-27, cytokines with divergent functions, Nat Rev Immunol 5 (2005): 521-531.
  16. Trinchieri G. Interlukin-12 and regulation of innate resistance and adaptive immunity, Nat Rev Immunol 3 (2003), pp.133-146.
  17. Dorman S.E and Holland S.M. Mutation in the signal-transducing chain of the interferon-gamma receptor and susceptility to mycobacterial infection, J Clin Invest 101 (1998), pp.2364-2369.
  18. Rodrigues LC, Diwan VK, Wheeler JG. Protective effect of BCG against tuberculous meningitis and miliary tuberculosis: a meta-analysis. Int J Epidemiol. 1993;22:1154 -1158.
  19. Lotte A, Wasz-Hockert O, Poisson N, et al. Second IUATLD study on complications induced by intradermal BCG vaccination. Bull Int Union Tuberc Lung Dis. 1988;63:47-59.
  20. Uysal G, Guven MA, Sanal O. Subcutaneous nodules as presenting sign of disseminated BCG infection in a SCID patient. Infection. 1999;27(4-5):293-4.
  21. Huang LH, Shyur SD, Weng JD, Shin-Chi, Tzen CY, Huang FY. Disseminated Bacille Calmette-Guerin disease as the initial presentation of X-linked severe combined immunodeficiency--a case report. Asian Pac J Allergy Immunol. 2005; 23(4):221-6.
  22. Clark M, Cameron DW. The benefits and risks of bacille Calmette-Guerin vaccination among infants at high risk for both tuberculosis and severe combined immunodeficiency: assessment by Markov model. BMC Pediatr. 2006 3;6:5.
  23. Liberek A, Korzon M, Bernatowska E, Kurenko-Deptuch M, Rytlewska M. Vaccination-related Mycobacterium bovis BCG infection. Emerg Infect Dis J. 2006 ;12(5):860-2.
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Soheila K, Parisa A, Reza M B, Baghaie N, Ali A K, Davood M. INHERITABLE DISORDERS OF INTERFERON-12 PATHWAY: DIAGNOSIS AND MANAGEMENT . Pediatric Oncall [serial online] 2008[cited 2008 May 1];5. Art #18. Available From : http://www.pediatriconcall.com/Journal/Article/FullText.aspx?artid=95&type=J&tid=&imgid=&reportid=276&tbltype=
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