Chronic granulomatous disease. Report on a national registry of 368 patients

Chronic granulomatous disease

Chronic granulomatous disease (CGD) is a primary immunodeficiency that affects phagocytes of the innate immune system and is characterized by a greatly increased susceptibility to severe bacterial and fungal infections. CGD is caused by mutations in any one of four genes that encode the subunits of phagocyte NADPH oxidase, the enzyme that generates microbicidal (and pro-inflammatory) oxygen radicals. Of the 410 CGD mutations identified, 95% cause the complete or partial loss of protein and provide little information regarding the relationship between protein structure and function. The remaining 5%, however, result in normal levels of inactive protein and many have provided valuable insights into the function of affected subunits and their roles in oxidase regulation and catalysis. Moreover, recent CGD studies have revealed that recombination events between the p47-phox gene (NCF-1) and its pseudogenes not only cause the absence of p47-phox, but also predict the generation of a novel fusion protein.

Genetic variation and hematology: single-nucleotide polymorphisms, haplotypes, and complex disease

In the course of generating a draft sequence of the human genome, we now recognize the enormous scope of genetic variation among humans, which can be used to probe the genetics of complex diseases such as leukemia or thrombosis. There is already mounting evidence of new susceptibility genes and genes that interact with environmental factors. Genetic variants, especially single-nucleotide polymorphisms (SNPs), also can be utilized to investigate potential modifiers of disease. Genetic variation can be applied to study pharmacogenomics, which could eventually drive the choice of therapeutic and interventional strategies. The genomic revolution ultimately should give insights into key mechanisms in hematological disorders that can be translated into targeted therapies.

Immune deficiency and autoimmunity

Immunodeficiency and autoimmune phenomena may occur concomitantly in the same individual. Many immune deficiency syndromes, mainly humoral defects, are associated with autoimmune disorders. Hematological manifestations, such as thrombocytopenia and hemolytic anemia, are the most common presentation, but many other autoimmune mediated conditions have also been described. Persistent antigen stimulation, due to an inherently defective immune system ability to eradicate pathogenesis is the primary cause leading to autoimmunity in patients with primary immunodeficiency states. Other factors leading to the increase incidence of autoimmune manifestion will be discussed in the present review. Treatment with intravenous gammagluobuilin may ameliorate the autoimmune disorder and bone marrow transplantation can cure both conditions.

Differential effect of p47phox and gp91phox deficiency on the course of Pneumococcal Meningitis

Bacterial meningitis is a severe inflammatory disease of the central nervous system and is characterized by massive infiltration of granulocytes into the cerebrospinal fluid (CSF). To assess the role of NADPH oxidase-derived reactive oxygen species (ROS) in pneumococcal meningitis, mice deficient in either the gp91 subunit (essential for functioning of the phagocyte enzyme) or the p47 subunit (essential for functioning of homologous enzymes in nonphagocytic cells) were intracisternally infected with live Streptococcus pneumoniae, and defined disease parameters were measured during the acute stage of infection. While none of the parameters measured (including CSF bacterial titers) were significantly different in gp91(-/-) and wild-type mice, the infection in p47(-/-) mice was associated with significantly increased inflammation of the subarachnoid and ventricular space, disruption of the blood-brain barrier, and the presence of interleukin-1 beta, tumor necrosis factor alpha, and matrix metalloproteinase 9 in the cortex. These changes were associated with approximately 10-fold-higher CSF bacterial titers in p47(-/-) mice than in wild-type mice (P < 0.001). In contrast to infection with live bacteria, the inflammatory response, including CSF leukocytosis, was significantly attenuated in p47(-/-) mice (but not gp91(-/-) mice) challenged with a fixed number of heat-inactivated pneumococci. Impairment of the host defense appeared to be responsible for the higher bacterial titers in p47(-/-) mice. Therefore, these results indicate that ROS generated by a gp91-independent NADPH oxidase(s) are important for establishing an adequate inflammatory response to pneumococcal CSF infection.

Itraconazole to prevent fungal infections in chronic granulomatous disease

BACKGROUND

Chronic granulomatous disease is a rare disorder in which the phagocytes fail to produce hydrogen peroxide. The patients are predisposed to bacterial and fungal infections. Prophylactic antibiotics and interferon gamma have reduced bacterial infections, but there is also the danger of life-threatening fungal infections. We assessed the efficacy of itraconazole as prophylaxis against serious fungal infections in chronic granulomatous disease.

METHODS

Thirty-nine patients at least 5 years old (6 female and 33 male; mean age, 14.9 years) were enrolled in a randomized, double-blind, placebo-controlled study. After the initially assigned treatment, each patient alternated between itraconazole and placebo annually. Patients 13 years of age or older and all patients weighing at least 50 kg received a single dose of 200 mg of itraconazole per day; those less than 13 years old or weighing less than 50 kg received a single dose of 100 mg per day. The primary end point was severe fungal infection, as determined by histologic results or culture.

RESULTS

One patient (who had not been compliant with the treatment) had a serious fungal infection while receiving itraconazole, as compared with seven who had a serious fungal infection while receiving placebo (P=0.10). No patient receiving itraconazole but five patients receiving placebo had a superficial fungal infection. No serious toxic effects were noted, although one patient had a rash and another had elevated results on liver-function tests; both of these effects resolved with the discontinuation of itraconazole.

CONCLUSIONS

Itraconazole prophylaxis appears to be an effective and well-tolerated treatment that reduces the frequency of fungal infections in chronic granulomatous disease, but monitoring for long-term toxic effects is warranted.

Killing of Aspergillus fumigatus by alveolar macrophages is mediated by reactive oxidant intermediates

Phagocytosis and mechanisms of killing of Aspergillus fumigatus conidia by murine alveolar macrophages (AM), which are the main phagocytic cells of the innate immunity of the lung, were investigated. Engulfment of conidia by murine AM lasts 2 h. Killing of A. fumigatus conidia by AM begins after 6 h of phagocytosis. Swelling of the conidia inside the AM is a prerequisite for killing of conidia. The contributions of NADPH oxidase and inducible nitric oxide synthase to the conidicidal activity of AM were studied using AM from OF1, wild-type and congenic p47phox(-/-) 129Sv, and wild-type and congenic iNOS(-/-) C57BL/6 mice. AM from p47phox(-/-) mice were unable to kill A. fumigatus conidia. Inhibitors of NADPH oxidase that decreased the production of reactive oxidant intermediates inhibited the killing of A. fumigatus without altering the phagocytosis rate. In contrast to NADPH oxidase, nitric oxide synthase does not play a role in killing of conidia. Corticosteroids did not alter the internalization of conidia by AM but did inhibit the production of reactive oxidant intermediates and the killing of A. fumigatus conidia by AM. Impairment of production of reactive oxidant intermediates by corticosteroids is responsible for the development of invasive aspergillosis in immunosuppressed mice.

Trichosporon pullulans infection in 2 patients with chronic granulomatous disease: an emerging pathogen and review of the literature

BACKGROUND

Chronic granulomatous disease is a genetically determined primary immunodeficiency disease in which phagocytic cells are unable to kill certain bacteria and fungi after ingestion. Manifestations include recurrent pyogenic infections caused by catalase-positive microbes. Trichosporon species are emerging as opportunistic agents that cause systemic disease in immunocompromised patients. Typically disease has been described in association with T beigelii in patients with secondary immunodeficiency, such as underlying malignancy.

OBJECTIVE

The objective was to report the first 2 cases of T pullulans infection in 2 male children with chronic granulomatous disease.

METHODS

The records of the 2 patients were reviewed. In addition, all cases of T pullulans infection reported in the English language literature are presented.

RESULTS

This report brings to 7 the total number of cases of T pullulans reported and the first in patients with chronic granulomatous disease, one with invasive pneumonia and the other with an infected paronychium and localized cellulitis. In the 5 additional cases malignancy was the principal risk factor.

CONCLUSION

T pullulans has rarely been reported as a fungal pathogen. The most prominent risk factor for the development of trichosporonosis is immunocompromise, most notably with neutropenia. Abnormally functioning neutrophils, such as with chronic granulomatous disease, may also predispose individuals to this opportunistic pathogen.

Perceptions of reproductive risk and carrier testing among adolescent sisters of males with chronic granulomatous disease

Although recent research has investigated the attitudes of parents, professionals, and adult siblings toward carrier testing of minors, no studies have focused on the experiences of minor siblings of individuals with X-linked and autosomal recessive conditions. To explore adolescent sisters' perceptions of their reproductive risks, attitudes toward carrier testing, and resources for information and support, we interviewed 14 parents and 9 sisters (ages 12-15) of males with chronic granulomatous disease (CGD), a primary immunodeficiency disorder inherited in both an X-linked recessive and autosomal recessive fashion. Our semistructured telephone interviews were audiotaped, transcribed, and subjected to template analysis (a common qualitative methodology). Girls were all aware that CGD is an inherited condition and each had made an assessment of her reproductive risk. All girls considered their parents to be their best source of information and support, but girls had trouble initiating discussions for fear of upsetting their parents. All girls and parents considered eventual carrier testing vital for reproductive decision-making and relationship-building. However, girls favored carrier testing at a later age and expressed more concerns about psychological risks associated with testing than did their parents. When faced with the hypothetical situation of being offered carrier testing "tomorrow," half of the parents and untested daughters disagreed on the desirability of the test, with parents more likely to favor testing. Including adolescent sisters in family-based genetic counseling that provides an opportunity for age-appropriate discussion of inheritance and the timing, risks, and benefits of carrier testing would be beneficial to them. Published 2003 Wiley-Liss, Inc.

Long-term high-level reconstitution of NADPH oxidase activity in murine X-linked chronic granulomatous disease using a bicistronic vector expressing gp91phox and a Delta LNGFR cell surface marker

A murine model of X-linked chronic granulomatous disease (X-CGD), an inherited immune deficiency with absent phagocyte NADPH oxidase activity caused by defects in the gp91(phox) gene, was used to evaluate a bicistronic retroviral vector in which expression of human gp91(phox) and a linked gene for Delta LNGFR, a truncated form of human low-affinity nerve growth factor receptor, are under the control of a spleen focus-forming virus long-terminal repeat (LTR). Four independent cohorts of 11-Gy irradiated X-CGD mice (total, 22 mice) were transplanted with or without preselection of transduced X-CGD bone marrow (BM). Transplanted mice had high-level correction of neutrophil gp91(phox) expression and reconstitution of NADPH oxidase activity. Expression lasted for at least 14 months in primary transplants, and persisted in secondary and tertiary transplants. Both gp91(phox) and Delta LNGFR were detected on circulating granulocytes, lymphocytes, lymphoid, and (for Delta LNGFR) red blood cells. Mice receiving transduced bone marrow [BM] preselected ex vivo for Delta LNGFR expression had high-level (= 80%) reconstitution with transduced cells, with an improved fraction of oxidase-corrected neutrophils posttransplant. Analysis of secondary and tertiary CFU-S showed that silencing of individual provirus integrants can occur even after preselection for Delta LNGFR prior to transplantation, and that persistent provirus expression was associated with multiple integration sites in most cases. No obvious adverse consequences of transgenic protein expression were observed.

Cut it out: Managing hepatic abscesses in patients with chronic granulomatous disease

BACKGROUND

Hepatic abscesses develop in patients with chronic granulomatous disease (CGD) because the liver is a site of constant bacterial challenge. The authors investigated the roles of drainage and hepatic resection in the management of liver abscesses in CGD patients.

METHODS

Medical records of CGD patients with hepatic abscesses from 1990 to 2001 were reviewed.

RESULTS

There were 6 patients. Mean age of initial abscess was 7.2 years (range, 3 weeks to 18.9 years). All abscesses involved the right lobe of the liver (2 single, 4 multiple). All patients received appropriate antibiotics. Four patients were treated with one to 6 drainage procedures over one to 4 admissions before ultimately undergoing resection. The other 2 patients underwent primary resection without preliminary drainage. Of the 6 resections, 4 were nonanatomic, and 2 were anatomic. There was one major postoperative complication (bleeding) requiring reoperation. There were no recurrences after resection (mean follow-up 4.3 yr). Mean total days in hospital for the treatment of liver abscess was 49 in the preliminary drainage group and 8.5 in the primary resection group. Three patients required admission into the intensive care unit, one after a drainage procedure and 2 after resection.

CONCLUSIONS

For CGD patients with hepatic abscesses, drainage procedures are associated with recurrence and prolonged hospitalization. Primary hepatic resection removing all involved tissue is safe and definitive for the management of this problem.

High glucose impairs superoxide production from isolated blood neutrophils

OBJECTIVE

Superoxide (O(2)(-)), a key antimicrobial agent in phagocytes, is produced by the activity of NADPH oxidase. High glucose concentrations may, however, impair the production of O(2)(-) through inhibition of glucose-6-phosphate dehydrogenase (G6PD), which catalyzes the formation of NADPH. This study measured the acute effects of high glucose or the G6PD inhibitor dehydroepiandrosterone (DHEA) on the production of O(2)(-) from isolated human neutrophils.

DESIGN

Laboratory studies of short-term cultures of neutrophil granulocytes.

PARTICIPANTS

Healthy subjects.

INTERVENTIONS

Neutrophils were isolated from peripheral blood and incubated for 1 h in Krebs-Ringer buffer containing 5, 10, or 25 mM glucose, 5 mM glucose with 0, 5, or 20 mM mannitol, or 5 mM glucose with 0, 1, 10, or 100 micro M DHEA. O(2)(-) production was induced by N-formyl-methionyl-leucyl-phenylalanine and measured by the cytochrome c reduction assay. Potential scavenging of O(2)(-) by glucose, mannitol, or DHEA was assessed in a cell free system using the pyrogallol assay.

MEASUREMENTS AND RESULTS

Incubation of neutrophils with glucose dose-dependently reduced O(2)(-) production, which was 50% decreased at 25 mM glucose. Also DHEA reduced the production of O(2)(-) dose-dependently, whereas production rates were unaffected by mannitol. Neither glucose, mannitol, nor DHEA scavenged O(2)(-).

CONCLUSIONS

High extracellular glucose concentrations acutely reduce O(2)(-) production from activated neutrophils possibly through inhibition of G6PD. If this occurs in vivo, microbial killing by neutrophils may be impaired during acute hyperglycemia, as observed after major surgery, trauma, or severe infection.

Infections with Haemophilus species in chronic granulomatous disease: insights into the interaction of bacterial catalase and H2O2 production

Chronic granulomatous disease (CGD) is a rare inherited disorder in which phagocytes are incapable of generating bactericidal-reactive oxygen derivatives. Typically these patients are susceptible to life-threatening infections with catalase-producing organisms. Haemophilus species, particularly H. paraphrophilus, are not associated with CGD infections, because these organisms rarely if ever produce catalase. Haemophilus species are part of the indigenous oral microbial flora and, other than H. influenzae, are rarely recognized as pathogens. They are fastidious and require additional growth factors and capnophilic culture conditions for optimal growth and identification. Here we describe three cases of infection with non-H. influenzae (NHI) Haemophilus species in CGD patients. These organisms were catalase-negative and therefore not expected to be virulent in CGD patients, but they were also H(2)O(2) production-negative, thereby negating the putative loss of virulence of being catalase-negative. These are the first reports of NHI Haemophilus species in CGD and reinforce the critical need for careful microbiologic evaluation of infections in CGD patients.

Immunomodulation of invasive fungal infections

Genetic and acquired (disease- or therapy- related) host immune factors increase the risk for IFIs. In addition to antifungal drug therapy, modulation of host defenses by the use of HGFs and IFN-gamma has been supported by extensive in vitro and in vivo preclinical data. Clinical studies on the prevention or the adjunctive therapy of IFIs in combination with antifungal agents are limited, however, and do not allow specific recommendations for their cost-effective use in most of the immunodeficient settings. There is an urgent need to push forward with well-structured, randomized clinical trials to determine optimal dose, duration, and timing for different combinations of immunotherapy and antifungal agents in high-risk patients.

Successful umbilical cord blood stem cell transplantation for chronic granulomatous disease

Chronic granulomatous disease (CGD) causes growth failure, inflammatory lung damage and often early death. Prophylactic cotrimoxazole improves medium-term survival, but cannot prevent inflammatory sequelae. We report the first patient with CGD who underwent successful HLA identical sibling umbilical cord stem cell transplantation (UCSCT) after myeloablative conditioning. The patient presented with colitis, confirmed as CGD at 2 years of age. Following BU16/CY200 conditioning, he had UCSCT from his unaffected HLA identical sister. A year post-transplant, his colitis had resolved clinically and on radioisotope scan growth has improved. Neutrophil oxidative burst was 92% normal with full donor lymphocyte reconstitution.

Diagnostic paradigm for evaluation of male patients with chronic granulomatous disease, based on the dihydrorhodamine 123 assay

BACKGROUND

Chronic granulomatous disease (CGD) is a phagocyte disorder caused by mutations in nicotinamide dinucleotide phosphate (NADPH) oxidase subunits. The dihydrorhodamine 123 (DHR) assay is an effective test for CGD that for most patients also might help to differentiate between the 2 most common forms, X-linked (X) gp91(phox) defect CGD and autosomal recessive (AR) p47(phox) defect CGD. However, some male patients with X-CGD have DHR patterns that overlap the AR-CGD pattern.

OBJECTIVE

The purpose of this investigation was to develop a diagnostic paradigm to delineate male patients with X-CGD expressing a DHR pattern suggestive of p47(phox) deficiency.

METHODS

The DHR assay measured change in fluorescence of DHR-loaded granulocytes after phorbol myristate acetate (PMA) stimulation. Western blot analysis measured the presence of NADPH oxidase subunits gp91(phox), p47(phox), p67(phox), and p22(phox). CYBB exonic sequencing was performed on PCR-amplified genomic DNA through use of intronic flanking primers. Ferricytochrome-c assay evaluated specific superoxide production by PMA-stimulated granulocytes.

RESULTS

Although 83% of patients with X-CGD have virtually no neutrophil DHR activity, we found that 17% of patients, proven to have X-CGD by other criteria, have modest DHR activity that is most consistent with p47(phox) deficiency. We describe a diagnostic paradigm to deal with such patients, and we present 2 cases, along with results of additional studies, including carrier evaluation, protein assessment, and mutation analysis, that are useful in establishing the genotype under these circumstances. DHR assays from the 2 patients described showed a fluorescence shift most characteristic of p47(phox)-AR-CGD; however, each of the patients' mothers showed mosaicism with a bimodal DHR pattern. Patient 1 had some gp91(phox) protein with a Y41D mutation and modest superoxide activity. Patient 2 had a normal level of gp91(phox) protein with a C537R mutation without detectable superoxide activity, as determined by ferricytochrome-c assay, despite the modest DHR activity.

CONCLUSIONS

Evaluation of male patients with CGD with modest DHR activity should initially include evaluation of potential female carriers for mosaicism with the use of the DHR assay. In circumstances in which this is uninformative, patients should be referred to centers capable of additional testing, including Western blot analysis and CYBB mutation analysis, to clarify the disease genotype.

Arthritis and osteomyelitis due to Aspergillus fumigatus: a 17 years old boy with chronic granulomatous disease

BACKGROUND

Invasive Aspergillus infections are frequently seen in immunocompromised patients but arthritis is a rare complication of Aspergillus infections in the absence of immune suppressive therapy, trauma or surgical intervention.

CASE PRESENTATION

A 17 years old male patient with arthritis and patellar osteomyelitis of the left knee whose further investigations revealed chronic granulomatous disease as the underlying disease is followed. Aspergillus fumigatus was isolated from the synovial fluid and the tissue samples cultures. He was treated with Amphotericin B deoxicolate 0.7 mg/kg/day. Also surgical debridement was performed our patient. Amphotericin B nephrotoxicity developed and the therapy switched to itraconazole 400 mg/day. Itraconazole therapy were discontinued at the 6th month. He can perform all the activities of daily living including.

CONCLUSION

We think that, chronic granulomatous disease should be investigated in patients who have aspergillar arthritis and osteomyelitis.

Construction of a deep-rough mutant of Burkholderia cepacia ATCC 25416 and characterization of its chemical and biological properties

Burkholderia cepacia is a bacterium with increasing importance as a pathogen in patients with cystic fibrosis. The deep-rough mutant Ko2b was generated from B. cepacia type strain ATCC 25416 by insertion of a kanamycin resistance cassette into the gene waaC encoding heptosyltransferase I. Mass spectrometric analysis of the de-O-acylated lipopolysaccharide (LPS) of the mutant showed that it consisted of a bisphosphorylated glucosamine backbone with two 3-hydroxyhexadecanoic acids in amide-linkage, 4-amino-4-deoxyarabinose (Ara4N) residues on both phosphates, and a core oligosaccharide of the sequence Ara4N-(1 --> 8) D-glycero-D-talo-oct-2-ulosonic acid (Ko)-(2 --> 4)3-deoxy-D-manno-oct-2-ulosonic acid (Kdo). The mutant allowed investigations on the biosynthesis of the LPS as well as on its role in human infection. Mutant Ko2b showed no difference in its ability to invade human macrophages as compared with the wild type. Furthermore, isolated LPS of both strains induced the production of tumor necrosis factor alpha from macrophages to the same extent. Thus, the truncation of the LPS did not decrease the biological activity of the mutant or its LPS in these aspects.

Direct estimates of human per nucleotide mutation rates at 20 loci causing Mendelian diseases

I estimate per nucleotide rates of spontaneous mutations of different kinds in humans directly from the data on per locus mutation rates and on sequences of de novo nonsense nucleotide substitutions, deletions, insertions, and complex events at eight loci causing autosomal dominant diseases and 12 loci causing X-linked diseases. The results are in good agreement with indirect estimates, obtained by comparison of orthologous human and chimpanzee pseudogenes. The average direct estimate of the combined rate of all mutations is 1.8x10(-8) per nucleotide per generation, and the coefficient of variation of this rate across the 20 loci is 0.53. Single nucleotide substitutions are approximately 25 times more common than all other mutations, deletions are approximately three times more common than insertions, complex mutations are very rare, and CpG context increases substitution rates by an order of magnitude. There is only a moderate tendency for loci with high per locus mutation rates to also have higher per nucleotide substitution rates, and per nucleotide rates of deletions and insertions are statistically independent on the per locus mutation rate. Rates of different kinds of mutations are strongly correlated across loci. Mutational hot spots with per nucleotide rates above 5x10(-7) make only a minor contribution to human mutation. In the next decade, direct measurements will produce a rather precise, quantitative description of human spontaneous mutation at the DNA level.

Long-term follow-up and prognosis of chronic granulomatous disease in Yugoslavia: is there a role for early bone marrow transplantation?

We report the long-term follow-up of 12 pediatric-aged patients with chronic granulomatous disease (CGD). The mean age at the onset of infections was 5 months with a median delay in diagnosis of 2.5 years. Bacille Calmette-Guérin lymphadenitis was the most common presenting infection (6) followed by suppurative lymphadenitis (4), liver abscess (1), or Salmonella sepsis (1). Prophylaxis with cotrimoxazole was recommended to all patients. During the mean follow-up of 10 years (range, 4-23 years) pneumonitis was the most prevalent infection (91%) followed by lymphadenitis (83%), aphtous stomatitis (58%), and liver abscesses (25%). Seven (58%) patients developed chronic lung disease due to grossly delayed diagnosis (3) or poor compliance with antimicrobial prophylaxis (4). Five (41%) patients died during the second decade of life of aspergillosis (3) or chronic lung disease (2). Probability of survival into the third decade of life was estimated to be only 19%. We argue that HLA-identical bone marrow transplantation (BMT), if possible, should be attempted at early age because of significant morbidity and mortality in adolescence. BMT also should be considered in patients who suffer severe infections despite antimicrobial prophylaxis or patients with evidence of chronic lung disease. Possibility of elective BMT from unrelated donors remains to be carefully evaluated.

Diminished T cell numbers in patients with chronic granulomatous disease

Chronic granulomatous disease is a neutrophil disorder in which phagocytic cells fail to produce a respiratory burst. Five genetic types of chronic granulomatous disease have been described and in each case the clinical manifestations relate to the inability to effectively kill catalase-positive organisms. It is classically described as a pure disorder of intracellular killing, with preservation of other aspects of phagocytic function such as migration and phagocytosis and normal function of nonmyeloid cells. This article describes a heretofore unrecognized feature of chronic granulomatous disease. Fifty-three patients with chronic granulomatous disease and 42 age-matched controls were studied by flow cytometry. Total T cell numbers and CD4 and CD8 T cell numbers were compared between patients and controls. Patients with chronic granulomatous disease had diminished T cell numbers compared to controls after 3 years of age. The difference increased with age. It is not known whether diminished T cell numbers influence the susceptibility to infections in these patients, but T cell effects could represent a significant cofactor for infection.

Immunodeficiency and genetic conditions that cause arthritis in childhood

Many conditions can cause or be associated with arthritis in childhood. The authors of this paper will review the situations in which underlying immunodeficiency or defective regulation of lymphocyte homeostasis must be suspected, and discuss, for some of these diseases, the genetic bases and pathogenesis. In the second part of this article, the authors will focus on other diseases that can cause arthritis in childhood, often with other symptoms, and for which evidence of an association with genetic abnormalities has been recently discovered. Finally, the authors will discuss the implications of recent findings regarding the role of some genes as causing or modulating factors in juvenile idiopathic arthritis and related disorders, as well as observations made in adults and in animal models of inflammation and autoimmunity.

A practical approach to neutrophil disorders

This review discusses disorders of altered neutrophil number and function and provide a basic framework for patient evaluation and management. The sections begin with neutropenia, neutrophilia and neutrophil dysfunction with a general screening approach to differentiate common, more benign syndromes from rare, often more serious disorders. Also included is a detailed discussion of some specific primary neutrophil syndromes at the end of each section. Focus is placed on specific disorders that are clinically common or particularly instructive.

Identification of a novel NCF-1 (p47-phox) pseudogene not containing the signature GT deletion: significance for A47 degrees chronic granulomatous disease carrier detection

The p47-phox gene, NCF-1, has 2 nearly identical pseudogenes (psiNCF-1) in proximity at chromosomal locus 7q11.23. A dinucleotide deletion (DeltaGT) at the beginning of exon 2 that leads to a frameshift and premature stop codon is considered the signature sequence of the pseudogenes. It is also the most prevalent mutation in p47-phox-deficient (A47 degrees ) chronic granulomatous disease (CGD) as a result of the insertion of a DeltaGT-containing fragment of pseudogene into NCF-1. Extending our study of the relationship between NCF-1 and psiNCF-1 to 53 unaffected control individuals, we found that although in most (n = 44), the ratio of pseudogene (DeltaGT) to functional gene (GTGT) sequence in amplicons spanning exon 2 was 2:1, as previously observed, surprisingly, in 7 persons the ratio was 1:1, and in 2 persons the ratio was 1:2. The lowered ratios are explained by the presence, in a heterozygous or homozygous state, respectively, of a pseudogene that contains GTGT rather than DeltaGT. It is possible that this pseudogene has not undergone deletion of GT, but more likely, based on analysis of additional NCF-1/psiNCF-1 markers, it represents the previously unidentified product of the reciprocal crossover of DNA fragments between the functional gene and one of its pseudogenes. The mutated NCF-1 resulting from this event is the predominant A47 degrees CGD allele. The existence of 2 extended haplotypes encompassing NCF-1/psiNCF-1 further complicates the detection of A47 degrees CGD carriers. Although most have a DeltaGT/GTGT ratio of 5:1, some have a ratio of 2:1 and are indistinguishable by this means from unaffected individuals.

Advances in Burkholderia cepacia complex

Burkholderia cepacia is an important opportunistic pathogen in certain compromised hosts, particularly those with either cystic fibrosis (CF) or chronic granulomatous disease. The "family" of bacteria known as B. cepacia is highly heterogeneous and is composed of at least nine discrete species or genomovars, constituting the B. cepacia complex. Bacteria from the B. cepacia complex are particularly virulent in susceptible hosts, often causing necrotising invasive infection and death. Whereas the microbial determinants of virulence in B. cepacia complex are currently not defined, the bacteria appear to have features facilitating survival within host cells. Burkholderia cepacia is highly resistant to antibiotics and to neutrophil-mediated non-oxidative killing; infection should be treated with combination antimicrobial therapy. Burkholderia cepacia can spread from one CF patient to another. Transmission appears to be facilitated by close personal contact and by certain bacterial factors.

Nocardia infection in chronic granulomatous disease

To determine the clinical characteristics and outcome of Nocardia infection in patients with chronic granulomatous disease (CGD), we reviewed data on 28 episodes of Nocardia infection in 23 patients with CGD. All episodes involved pulmonary infection. The frequency of disseminated nocardiosis was 25% for the case series overall, but it was 56% among episodes in patients receiving neither interferon-gamma (IFN-gamma) nor sulfonamide prophylaxis. Patients receiving prophylaxis with IFN-gamma and/or a sulfonamide were significantly less likely to have disseminated nocardiosis than were patients not receiving these medications, and no patient receiving both medications developed disseminated nocardiosis. One-third of the patients had concomitant fungal infections, and 2 patients had concomitant Legionella infections. The majority of patients were successfully treated with a sulfonamide-containing regimen, even though some patients had developed Nocardia infection while receiving sulfonamide prophylaxis. Nocardia infections in patients with CGD are not usually fatal if treated properly, and prophylaxis with IFN-gamma and a sulfonamide may protect against dissemination.

The role of the gut flora in health and disease, and its modification as therapy

The gut flora is a vast interior ecosystem whose nature is only beginning to be unravelled, due to the emergence of sophisticated molecular tools. Techniques such as 16S ribosomal RNA analysis, polymerase chain reaction amplification and the use of DNA microarrays now facilitate rapid identification and characterization of species resistant to conventional culture and possibly unknown species. Life-long cross-talk between the host and the gut flora determines whether health is maintained or disease intervenes. An understanding of these bacteria-bacteria and bacteria-host immune and epithelial cell interactions is likely to lead to a greater insight into disease pathogenesis. Studies of single organism-epithelial interactions have revealed the large range of metabolic processes that gut bacteria may influence. In inflammatory bowel diseases, bacteria drive the inflammatory process, and genetic predisposition to disease identified to date, such as the recently described NOD2/CARD15 gene variants, may relate to altered bacterial recognition. Extra-intestinal disorders, such as atopy and arthritis, may also have an altered gut milieu as their basis. Clinical evidence is emerging that the modification of this internal environment, using either antibiotics or probiotic bacteria, is beneficial in preventing and treating disease. This natural and apparently safe approach holds great appeal.

CYBB mutation analysis in X-linked chronic granulomatous disease

Chronic granulomatous disease (CGD) results from mutations of phagocyte NADPH oxidase. Seventy percent are X-linked (X-)CGD with absent or defective gp91(phox) protein encoded by the CYBB gene. A subset of X-CGD patients demonstrates partial oxidase activity and/or varied levels of the gp91(phox) protein. Definitive genotypic diagnosis in these unusual patients requires mutation analysis. Typically, CYBB mutation analysis has relied on initial screening of cDNA by single-stranded conformation polymorphism analysis, followed by selective sequencing. We report a fluorescent, automated method for CYBB mutation analysis using genomic DNA that provides more rapid and reliable results. Moreover, the use of genomic DNA in this approach allows mutation detection in the mRNA coding region, promoter/enhancer region, and intronic sequences flanking splice junctions and does not require mRNA preparation. The PCR conditions were optimized for each exon, including those with A+T-rich regions. We analyzed DNA from two unusual X-CGD patients and established the genetic basis for their phenotype. We also sequenced 100 normal X chromosomes to establish wild-type consensus sequences and identify polymorphisms.

Genetic dissection of immunity to mycobacteria: the human model

Humans are exposed to a variety of environmental mycobacteria (EM), and most children are inoculated with live Bacille Calmette-Guérin (BCG) vaccine. In addition, most of the world's population is occasionally exposed to human-borne mycobacterial species, which are less abundant but more virulent. Although rarely pathogenic, mildly virulent mycobacteria, including BCG and most EM, may cause a variety of clinical diseases. Mycobacterium tuberculosis, M. leprae, and EM M. ulcerans are more virulent, causing tuberculosis, leprosy, and Buruli ulcer, respectively. Remarkably, only a minority of individuals develop clinical disease, even if infected with virulent mycobacteria. The interindividual variability of clinical outcome is thought to result in part from variability in the human genes that control host defense. In this well-defined microbiological and clinical context, the principles of mouse immunology and the methods of human genetics can be combined to facilitate the genetic dissection of immunity to mycobacteria. The natural infections are unique to the human model, not being found in any of the animal models of experimental infection. We review current genetic knowledge concerning the simple and complex inheritance of predisposition to mycobacterial diseases in humans. Rare patients with Mendelian disorders have been found to be vulnerable to BCG, a few EM, and M. tuberculosis. Most cases of presumed Mendelian susceptibility to these and other mycobacterial species remain unexplained. In the general population leprosy and tuberculosis have been shown to be associated with certain human genetic polymorphisms and linked to certain chromosomal regions. The causal vulnerability genes themselves have yet to be identified and their pathogenic alleles immunologically validated. The studies carried out to date have been fruitful, initiating the genetic dissection of protective immunity against a variety of mycobacterial species in natural conditions of infection. The human model has potential uses beyond the study of mycobacterial infections and may well become a model of choice for the investigation of immunity to infectious agents.

Amphotericin B formulations exert additive antifungal activity in combination with pulmonary alveolar macrophages and polymorphonuclear leukocytes against Aspergillus fumigatus

Deoxycholate amphotericin B (DAMB) and amphotericin B lipid complex (ABLC) additively augmented the fungicidal activity of pulmonary alveolar macrophages against the conidia of Aspergillus fumigatus. DAMB, ABLC, and liposomal amphotericin B similarly displayed additive effects with polymorphonuclear leukocytes in damaging the hyphal elements of A. fumigatus.

Autoimmunity in human primary immunodeficiency diseases

Human primary immunodeficiency diseases are experiments of nature characterized by an increased susceptibility to infection. In many cases, they are also associated with troublesome and sometimes life-threatening autoimmune complications. In the past few years, great strides have been made in understanding the molecular basis of primary immunodeficiencies, and this had led to more focused and successful treatment. This review has 3 aims: (1) to highlight the variety of autoimmune phenomena associated with human primary immunodeficiency diseases; (2) to explore how primary immunodeficiencies predispose patients to autoimmune phenomena triggered by opportunistic infections; and (3) to consider the rationale for the current treatment strategies for autoimmune phenomena, specifically in relation to primary immunodeficiency diseases. Reviewing recent advances in our understanding of the small subgroup of patients with defined causes for their autoimmunity may lead to the development of more effective treatment strategies for idiopathic human autoimmune diseases.

Neutropenia associated with primary immunodeficiency syndromes

The primary immunodeficiency diseases are a heterogeneous group of more than 75 disorders characterized by intrinsic defects in the functions of the immune system. Many are associated with abnormalities of hematopoiesis as well. This article will review those primary immunodeficiency syndromes in which neutropenia is a prominent finding, including X-linked agammaglobulinemia (XLA), hyper IgM syndrome, common variable immunodeficiency (CVID), IgA deficiency, cartilage-hair hypoplasia (CHH), and reticular dysgenesis, with regards to pathophysiologic findings and treatment.

Perianal rhabdomyosarcoma presenting as a perirectal abscess: A report of 11 cases

BACKGROUND PURPOSE

The organs and soft tissues of the pelvis are some of the most common primary sites for rhabdomyosarcoma (RMS) in children and adolescents. In most cases a mass is detectable on clinical examination, and the initial concern is focused on the possibility of a neoplasm. The current report concerns 11 patients, each presented with a painful perineal-perianal mass suggesting an abscess to the extent that each one of these patients was treated initially with antibiotics or incision and drainage for several weeks to months before the pathologic diagnosis of RMS was established.

METHODS

The authors reviewed the clinical histories of all patients with perirectal/perianal RMS from their respective institutions to identify cases in which the initial clinical diagnosis or impression was that of a perirectal abscess. Pathologic material was reviewed in all cases.

RESULTS

Eleven patients, 7 of whom were girls, ranged in age from 1 to 16 years at diagnosis (median age, 14 years). Fever accompanied the clinical presentation in 2 patients. None of the patients had a past medical history of illness that may have predisposed them to a perirectal abscess, although one patient had a family history of inflammatory bowel disease. Duration of symptoms ranged from 1 month to 1 year (mean, 4.6 months). Each patient presented with a tender perianal/perineal nodule or mass. Inguinal adenopathy was present in 6 patients at diagnosis. White blood cell counts ranged from 6,600/mm(3) to 24,500/mm(3). LDH levels ranged from 414 to 3,432 U/L. The average time from presentation to pathologic diagnosis of RMS was 2.1 months. Nine of the 11 cases showed an alveolar pattern. All were high-stage disease. Of 7 patients with follow-up longer than 1 year, 2 (29%) are alive without disease.

CONCLUSION

This report presents the need to consider the possibility of a malignant neoplasm, in this case RMS, in a child or adolescent with a putative perirectal abscess that fails to respond in the expected manner to incision and drainage and antibiotic therapy.

Innate immunity to Mycobacterium tuberculosis

The different manifestations of infection with Mycobacterium tuberculosis reflect the balance between the bacillus and host defense mechanisms. Traditionally, protective immunity to tuberculosis has been ascribed to T-cell-mediated immunity, with CD4(+) T cells playing a crucial role. Recent immunological and genetic studies support the long-standing notion that innate immunity is also relevant in tuberculosis. In this review, emphasis is on these natural, innate host defense mechanisms, referring to experimental data (e.g., studies in gene knockout mice) and epidemiological, immunological, and genetic studies in human tuberculosis. The first step in the innate host defense is cellular uptake of M. tuberculosis, which involves different cellular receptors and humoral factors. Toll-like receptors seem to play a crucial role in immune recognition of M. tuberculosis, which is the next step. The subsequent inflammatory response is regulated by production of pro- and anti-inflammatory cytokines and chemokines. Different natural effector mechanisms for killing of M. tuberculosis have now been identified. Finally, the innate host response is necessary for induction of adaptive immunity to M. tuberculosis. These basic mechanisms augment our understanding of disease pathogenesis and clinical course and will be of help in designing adjunctive treatment strategies.

Propionibacterium acnes chest infections in patients with chronic granulomatous disease: case reports

Antibiotic prophylaxis in patients with chronic granulomatous disease (CGD) has decreased the prevalence of infections, but uncommon microorganisms are being observed more frequently. Propionibacterium acnes, a saprophyte of the skin, is generally not involved in infections other than acne. Two cases of P. acnes extracutaneous infections in teenagers with CGD are reported.

Voriconazole in the treatment of aspergillosis, scedosporiosis and other invasive fungal infections in children

OBJECTIVE

To describe the safety and efficacy of voriconazole in children treated within the compassionate release program.

METHODS

Children received voriconazole on a compassionate basis for treatment of an invasive fungal infection if they were refractory to or intolerant of conventional antifungal therapy. Voriconazole was administered as a loading dose of 6 mg/kg every 12 h i.v. on Day 1 followed by 4 mg/kg every 12 h i.v. thereafter. When feasible the route of administration of voriconazole was changed from i.v. to oral (100 or 200 mg twice a day for patients weighing < 40 or > or = 40 kg, respectively). Outcome was assessed by investigators at the end of therapy or at the last visit as success (complete or partial response), stable infection, or failure, based on protocol-defined criteria.

RESULTS

Sixty-nine children (ages 9 months to 15 years; median, 7 years) received voriconazole; 58 had a proven or probable fungal infection. Among these 58 patients 27 had hematologic malignancies and 13 had chronic granulomatous disease as the most frequent underlying conditions. Forty-two patients had aspergillosis, 8 had scedosporiosis, 4 had invasive candidiasis and 4 had other invasive fungal infections. The median duration of voriconazole therapy was 93 days. At the end of therapy 26 patients (45%) had a complete or partial response. Four patients (7%) had a stable response, 25 (43%) failed therapy and 4 (7%) were discontinued from voriconazole because of intolerance. Success rates were highest in patients with chronic granulomatous disease (62%) and lowest in patients with hematologic malignancies (33%). Two patients experienced treatment-related serious adverse events (ulcerated lips with rash, elevated hepatic transaminases or bilirubin). A total of 23 patients had voriconazole-related adverse events, 3 (13%) of which caused discontinuation of voriconazole therapy. The most commonly reported adverse events included elevation in hepatic transaminases or bilirubin (n = 8), skin rash (n = 8), abnormal vision (n = 3) and a photosensitivity reaction (n = 3).

CONCLUSION

These data support the use of voriconazole for treatment of invasive fungal infections in pediatric patients who are intolerant of or refractory to conventional antifungal therapy.

Hepatic abscess in patients with chronic granulomatous disease

OBJECTIVE

To evaluate the clinical presentation, diagnostic procedures, and surgical management of hepatic abscesses in patients with chronic granulomatous disease (CGD).

SUMMARY BACKGROUND DATA

Chronic granulomatous disease is a rare inherited primary immunodeficiency in which phagocytes cannot destroy catalase-positive bacteria and fungi. Defects in the phagocytic cells' respiratory burst lead to life-threatening infections, including hepatic abscess. These abscesses are recurrent and often multiple and are treated differently from bacterial abscesses in patients without CGD.

METHODS

Between 1980 and 2000, 61 cases of hepatic abscess in 22 patients with CGD were treated at the National Institutes of Health. Clinicopathologic features were investigated by retrospective review of the medical records, radiographs, and histopathology.

RESULTS

Twelve of the 61 cases were primary hepatic abscesses. Twenty-nine of the cases were recurrent hepatic abscesses, and 20 cases were persistent hepatic abscesses. The median age at the time of initial hepatic abscess presentation was 14 years. Subjective fever was the most frequent presenting symptom, and the erythrocyte sedimentation rate was elevated in 98% of cases. Fifty-two cases were managed surgically and eight cases were managed with percutaneous drainage. One patient refused surgery. The surgical complication rate was 56%; however, there were no deaths directly related to the hepatic abscesses. Staphylococcus aureus was the most frequent organism identified in culture (88% of positive cultures). Aggressive surgery and antibiotics ultimately resulted in successful treatment of all patients.

CONCLUSIONS

Hepatic abscesses occurring in patients with CGD represent a difficult diagnostic and treatment challenge. Early excision and treatment with antibiotics directed against S. aureus is necessary. General surgeons should be aware of this rare immunodeficiency and should aggressively manage hepatic abscesses in these patients.

Fatal disseminated Candida lusitaniae infection in an infant with chronic granulomatous disease

A 3-month-old boy born to a mother carrying an X-linked form of chronic granulomatous disease presented with persistent fever and hepatosplenomegaly. The diagnosis was confirmed as a gp91phox defect by genetic analysis, and the patient was managed with broad spectrum antibacterial agents, gamma-interferon and later amphotericin B. A liver biopsy revealed granulomata with budding yeast forms, and cultures of blood and urine grew Candida lusitaniae. The patient died 26 days after admission.

Antioxidant enzyme expression in clinical isolates of Pseudomonas aeruginosa: identification of an atypical form of manganese superoxide dismutase

Expression of superoxide dismutases (FeSOD and MnSOD) and catalases by laboratory strains of Pseudomonas aeruginosa is modulated by exogenous factors. Whether clinical isolates behave similarly and whether antioxidant enzyme expression influences P. aeruginosa virulence remain unclear. Fifty-seven P. aeruginosa blood culture isolates, plus seven pairs of blood and local-site isolates, were examined for FeSOD, MnSOD, and catalase production in vitro. Under iron-replete growth conditions FeSOD and catalase activities were maximized. MnSOD was not detected. FeSOD and catalase activity decreased under iron-limited growth conditions, whereas MnSOD activity appeared. SOD and catalase activity did not change with site of isolation or by patient. MnSOD could not be expressed by one isolate due to a missense mutation in sodA that produced a premature stop codon. Eleven percent of the isolates expressed a novel, rapidly migrating MnSOD that was associated with missense mutations in the normal stop codon of sodA. We conclude that clinical P. aeruginosa isolates vary little in FeSOD and catalase expression. Some strains produce a newly described MnSOD variant, whereas one is deficient in MnSOD production. The absence of MnSOD expression in a P. aeruginosa strain causing invasive human disease indicates that MnSOD is probably not essential for P. aeruginosa virulence.

Mycobacterial diseases in primary immunodeficiencies

Primary immunodeficiency diseases comprise over 100 conditions, each associated with a variety of viral, bacterial, fungal and protozoan infections. M. tuberculosis and less virulent mycobacteria, such as bacille Calmette-Guérin vaccines and environmental non-tuberculous mycobacteria, may cause severe disease in patients with primary immunodeficiency diseases. However, no previous review has dealt with the issue of which primary immunodeficiency diseases predispose affected individuals to mycobacterial disease. This information is very useful, not only increasing our understanding of human immunity to mycobacteria, but also for the diagnostic investigation of patients with mycobacteriosis. We review here the medical literature on cases of mycobacterial disease in patients with primary immunodeficiency diseases.

Novel aspects of phagocytic cell disorders

This review highlights the various numerical and functional defects in the phagocyte system. It mainly focuses on newly discovered genetic defects in the system and the role played by these defects in the clinical symptoms presented by patients. Novel therapeutic modalities to treat phagocyte abnormalities, which are currently under clinical trials, are also discussed.

Keratitis caused by Candida glabrata in a patient with chronic granulomatous disease

PURPOSE

To report an unusual ocular presentation of Candida glabrata in a patient with chronic granulomatous disease.

METHODS

Interventional case report. A 15-year-old boy with chronic granulomatous disease presented with bilateral limbal infiltrates. He had been receiving broad-spectrum systemic antibiotics for recurrent liver abscesses. The keratitis did not respond to antibiotics and did not resolve after a course of topical steroids.

RESULTS

Corneal cultures revealed Candida glabrata. The same species was simultaneously isolated from the surgical drainage of the liver abscesses. The ocular and hepatic findings resolved on intravenous amphotericin B.

CONCLUSION

Candida glabrata has recently emerged as an important nosocomial pathogen. It may present as a limbal keratitis in the setting of systemic infection.

Gastrointestinal manifestations of primary immunodeficiencies

Congenital immunodeficiencies are relatively rare disorders that result in a marked predisposition to infection and to a variety of gastrointestinal problems. Increasingly recognized in both children and adults, accumulating worldwide experience with these disorders reveals that the long-term prognosis is poor in many cases, despite available treatments. This review highlights the past year's advances concerning the molecular basis of several of these disorders, new diagnostic considerations, and novel therapeutic approaches concerning their gastrointestinal complications. The availability of molecular diagnostic tools increases the options for earlier definitive treatments such as bone marrow transplantation and somatic gene therapy.

The immunologic workup of the child suspected of immunodeficiency

OBJECTIVE

This review is intended to provide an outline for the evaluation of patients suspected of having immunodeficiency, a problem that is frequently encountered in clinical practice.

DATA SOURCES

Information was obtained through a MEDLINE literature search as well as from standard textbooks in immunology. Also included is information that reflects the authors' clinical experience in the field.

RESULTS

In general clinical practice, many physicians feel inadequate to evaluate patients with suspected immune deficiencies. They also think that the process of evaluation is time-consuming, which results in misdiagnosis of a substantial percentage of such disorders. Hence, the prevalence of immunodeficiency disorders is much higher than generally thought. At present, there are >80 unique primary immunodeficiency conditions and >50 syndromes that are associated with various immunologic defects. The prevalence of secondary immunodeficiency has also been increasing because of the tragic epidemic of HIV infection, more usage of immunosuppressive medications and bone marrow stem cell transplantation, and the severe degree of malnutrition in underdeveloped countries. It is necessary for clinicians, particularly the specialists in allergy and immunology, to be able to evaluate the status of the immune system.

CONCLUSIONS

Very valuable information can be gathered from the medical history and physical examination that may exclude or increase the suspicion of immunologic defect. Laboratory tests can then be appropriately selected to define the specific defect. Once the diagnosis has been settled, proper medical management can be instituted with subsequent improvement in morbidity and mortality of such disorders.

Correction of genetic blood defects by gene transfer

Recent clinical trials in patients with a severe combined immunodeficiency disease demonstrate that gene therapy is a powerful tool in the treatment of genetic blood defects. Recent identification of the genes involved in the pathogenesis of inherited lymphohemopoietic disorders led to animal models of gene transfer. Extensive preclinical studies have overcome some of the obstacles involved in the transduction of hemopoietic cells. These promising results led to the approval of several clinical trials that are currently underway. This review focuses on the clinical outcome in patients with genetic blood defects treated by gene transfer and examines the progress achieved to date and the problems that have been encountered. Despite the obstacles, improved clinical results for several of these diseases are expected within the next 5 years.

Diagnostic and therapeutic impact of whole body positron emission tomography using fluorine-18-fluoro-2-deoxy-D-glucose in children with chronic granulomatous disease

AIMS

To compare whole body positron emission tomography (PET) using fluorine-18-fluoro-2-deoxy-D-glucose (FDG) with computed tomography (CT) in detecting active infective foci in children with chronic granulomatous disease.

METHODS

We performed 22 whole body FDG PET studies in seven children with X linked (n = 6) or autosomal recessive (n = 1) CGD. All had clinical signs of infection and/or were evaluated prior to bone marrow transplantation (BMT). Nineteen PET studies were also correlated with chest and/or abdominal CT. All PET scans were interpreted blinded to the CT findings. Diagnoses were confirmed histologically and bacteriologically.

RESULTS

We detected 116 lesions in 22 FGD PETs and 126 lesions on 19 CTs. Only two of the latter could be classified reliably as active lesions by virtue of contrast enhancement suggesting abscess formation. PET excluded 59 lesions suspicious for active infection on CT and revealed 49 infective lesions not seen on CT. All seven active infective lesions were identified by PET, allowing targeted biopsy and identification of the infective agent followed by specific antimicrobial treatment, surgery, or subsequent BMT.

CONCLUSIONS

Identification of infective organisms is more precise if active lesions are biopsied. CT does not discriminate between active and inactive lesions. Whole body FDG PET can be used to screen for active infective lesions in CGD patients.