DNA Repair Disorder Research Articles

The ubiquitous transcriptional protein ZNF143 activates a diversity of genes while assisting to organize chromatin structure.

Zinc Finger Protein 143 (ZNF143) is a pervasive C2H2 zinc-finger transcriptional activator protein regulating the efficiency of eukaryotic promoter regions. ZNF143 is able to activate transcription at both protein coding genes and small RNA genes transcribed by either RNA polymerase II or RNA polymerase III. Target genes regulated by ZNF143 are involved in an array of different cellular processes including both cancer and development. Although a key player in regulating eukaryotic genes, the molecular mechanism by with ZNF143 binds and activates genes transcribed by two different polymerases is still relatively unknown. In addition to its role as a transcriptional regulator, recent genomics experiments have implicated ZNF143 as a potential co-factor involved in chromatin looping and establishing higher order structure within the genome. This review focuses primarily on possible activation mechanisms of promoters by ZNF143, with less emphasis on the role of ZNF143 in cancer and development, and its function in establishing higher order chromatin contacts within the genome.

MYC Promotes Bone Marrow Stem Cell Dysfunction in Fanconi Anemia.

Bone marrow failure (BMF) in Fanconi anemia (FA) patients results from dysfunctional hematopoietic stem and progenitor cells (HSPCs). To identify determinants of BMF, we performed single-cell transcriptome profiling of primary HSPCs from FA patients. In addition to overexpression of p53 and TGF-β pathway genes, we identified high levels of MYC expression. We correspondingly observed coexistence of distinct HSPC subpopulations expressing high levels of TP53 or MYC in FA bone marrow (BM). Inhibiting MYC expression with the BET bromodomain inhibitor (+)-JQ1 reduced the clonogenic potential of FA patient HSPCs but rescued physiological and genotoxic stress in HSPCs from FA mice, showing that MYC promotes proliferation while increasing DNA damage. MYC-high HSPCs showed significant downregulation of cell adhesion genes, consistent with enhanced egress of FA HSPCs from bone marrow to peripheral blood. We speculate that MYC overexpression impairs HSPC function in FA patients and contributes to exhaustion in FA bone marrow.

Rare occurrence of coexistent squamous cell carcinoma and basal cell carcinoma in a case of Xeroderma Pigmentosum

Xeroderma Pigmentosum is an inherited disorder of DNA repair characterised by defective nucleotide excision repair, which is involved in repairing ultraviolet rays induced cross linking of pyramidine residues. Affected individuals are at increased risk of development of mucocutaneous cancers at a much earlier age than normal. This genodermatosis affects both sexes and all races. The incidence in India is still unknown. We report one such case of a nine year old boy with co-existent squamous cell carcinoma and basal cell carcinoma of the face.

The Phenotypic Spectrum of PNKP-Associated Disease and the Absence of Immunodeficiency and Cancer Predisposition in a Dutch Cohort

BackgroundWe aimed to expand the number of currently known pathogenic PNKP mutations, to study the phenotypic spectrum, including radiological characteristics and genotype-phenotype correlations, and to assess whether immunodeficiency and increased cancer risk are part of the DNA repair disorder caused by mutations in the PNKP gene. MethodsWe evaluated nine patients with PNKP mutations. A neurological history and examination was obtained. All patients had undergone neuroimaging and genetic testing as part of the prior diagnostic process. Laboratory measurements included potential biomarkers, and, in the context of a DNA repair disorder, we performed a detailed immunologic evaluation, including B cell repertoire analysis. ResultsWe identified three new mutations in the PNKP gene and confirm the phenotypic spectrum of PNKP-associated disease, ranging from microcephaly, seizures, and developmental delay to ataxia with oculomotor apraxia type 4. Irrespective of the phenotype, alpha-fetoprotein is a biochemical marker and increases with age and progression of the disease. On neuroimaging, (progressive) cerebellar atrophy was a universal feature. No clinical signs of immunodeficiency were present, and immunologic assessment was unremarkable. One patient developed cancer, but this was attributed to a concurrent von Hippel-Lindau mutation. ConclusionsImmunodeficiency and cancer predisposition do not appear to be part of PNKP-associated disease, contrasting many other DNA repair disorders. Furthermore, our study illustrates that the previously described syndromes microcephaly, seizures, and developmental delay, and ataxia with oculomotor apraxia type 4, represent the extremes of an overlapping spectrum of disease. Cerebellar atrophy and elevated serum alpha-fetoprotein levels are early diagnostic findings across the entire phenotypical spectrum.

Treosulfan-Based Conditioning Regimen in Haematopoietic Stem Cell Transplantation with TCRαβ/CD19 Depletion in Nijmegen Breakage Syndrome.

Nijmegen breakage syndrome (NBS) is a DNA repair disorder characterized by combined immunodeficiency and a high predisposition to malignancies. HSCT appears to cure immunodeficiency, but remains challenging due to limited experience in long-term risks of transplant-associated toxicity and malignancies. Twenty NBS patients received 22 allogeneic HSCTs with TCRαβ/CD19+ graft depletion with fludarabine 150mg/m2, cyclophosphamide 20-40mg/kg and thymoglobulin 5mg/kg based conditioning regimens (CRs). Twelve patients additionally received low-dose busulfan 4mg/kg (Bu group) and 10 patients (including 2 recipients of a second HSCT) treosulfan (Treo group) 30g/m2. Overall and event-free survival were 0.75 vs 1 (p =0.16) and 0.47 vs 0.89 (p =0.1) in the Bu and Treo groups, respectively. In the Bu group, four patients developed graft rejection, and three died: two died of de novo and relapsed lymphomas and one died of adenoviral hepatitis. The four living patients exhibited split chimerism with predominantly recipient myeloid cells and predominantly donor T and B lymphocytes. In Treo group, one patient developed rhabdomyosarcoma. There was no difference in the incidence of GVHD, viral reactivation, or early toxicity between either group. Low-dose Bu-containing CR in NBS leads to increased graft failure and low donor myeloid chimerism. Treo-CR followed by TCRαβ/CD19-depleted HSCT demonstrates a low level of early transplant-associated toxicity and enhanced graft function with stable donor chimerism.

261 Assessment of readthrough of premature termination codons in xeroderma pigmentosum group C patients by real-time PCR and immunohistochemistry

Xeroderma pigmentosum (XP) is a rare autosomal recessive DNA repair disorder caused by mutations in 8 genes, XP-A to XP-G, and Variant with severe sun sensitivity and10,000-fold increased risk of skin cancer. XP-C is the most common type in the U.S. About 12% of XP-C patients have premature termination codon (PTC) mutations that can lead to XPC protein elongation arrest and XPC mRNA template degradation by nonsense mediated decay. Our previous studies have shown treatment with aminoglycosides promote readthrough of PTC in XP-C cells. Amlexanox, an anti-inflammatory, antiallergic and immunomodulator, was reported to increase readthrough in human cells with PTC associated diseases. We treated parallel pairs of fibroblasts and lymphoblasts derived from two unrelated XP-C patients along with 2 normal control cells with amlexanox and/or previously tested aminoglycosides. Levels of XPC mRNA increased in XPC fibroblasts exposed to both G418 and amlexanox to a different extent in different cells. We are also developing a more direct assessment of level of XPC protein in human skin by use of immunohistochemistry with XPC antibodies. Two mm skin punch biopsies are stained with IHC and assessed microscopically. The slides are then scanned and the intensity of the staining is assessed by computer algorithm. In skin from normal donors XPC staining was prominent in the nuclei of epidermal cells and sweat glands in the dermis. In contrast, only background XPC staining was observed in cells from XPC patients. These preclinical tests are a step towards precision medicine that should assist patient selection and determining which drug combination would be optimal to increase XPC function for each patient.

106 XPC splice site founder mutation in families with xeroderma pigmentosum from Dominican Republic and Honduras

Xeroderma pigmentosum (XP) is a rare autosomal recessive DNA repair disorder. XP is caused by mutations in 7 nucleotide excision repair genes, XP-A to XP-G, and POLH gene involved in trans lesion synthesis pathway by which cells replicate across UV-induced DNA lesions. XP-C is the most common in the U.S. XP patients are highly sun-sensitive with 10,000-fold increased risk of skin cancer. In a cohort of 123 XP patients and their families enrolled at the National Institutes of Health (NIH), we identified a founder XPC splice site mutation (c.2251-1G>C) in 8 XP patients (4 from the Dominican Republic, 2 from Honduras and 2 from Tanzania). They all had extensive sun exposure with multiple skin cancers and severe ocular damage (blindness or ocular cancer). Seven XP patients were homozygous for the splice mutation and one was a compound heterozygote. Microsatellite analysis surrounding the XPC founder mutation indicates that these patients might share a common ancestor. This splice mutation has been reported as very frequent in parts of Africa (1/5,000 in Mayotte). This African XPC founder mutation may have been brought to the Dominican Republic and Central America as part of the slave trade that flourished in the 16th to 18th centuries. Other founder mutations have been reported in XP patients in Japan (XPA) and Morocco (XPC, TG-deletion). The increase in frequency of XPC founder mutations in Dominican Republic and Honduras would have public health implications. The early detection and rigorous UV protection can improve XP patient clinical outcomes in these countries.

Persistent DNA damage–induced NLRP12 improves hematopoietic stem cell function

NOD-like receptor 12 (NLRP12) is a member of the nucleotide-binding domain and leucine-rich repeat containing receptor inflammasome family that plays a central role in innate immunity. We previously showed that DNA damage upregulated NLRP12 in hematopoietic stem cells (HSCs) of mice deficient in the DNA repair gene Fanca. However, the role of NLRP12 in HSC maintenance is not known. Here, we show that persistent DNA damage-induced NLRP12 improves HSC function in both mouse and human models of DNA repair deficiency and aging. Specifically, treatment of Fanca-/- mice with the DNA cross-linker mitomycin C or ionizing radiation induces NLRP12 upregulation in phenotypic HSCs. NLRP12 expression is specifically induced by persistent DNA damage. Functionally, knockdown of NLRP12 exacerbates the repopulation defect of Fanca-/- HSCs. Persistent DNA damage-induced NLRP12 was also observed in the HSCs from aged mice, and depletion of NLRP12 in these aged HSCs compromised their self-renewal and hematopoietic recovery. Consistently, overexpression of NLRP12 substantially improved the long-term repopulating function of Fanca-/- and aged HSCs. Finally, persistent DNA damage-induced NLRP12 maintains the function of HSCs from patients with FA or aged donors. These results reveal a potentially novel role of NLRP12 in HSC maintenance and suggest that NLRP12 targeting has therapeutic potential in DNA repair disorders and aging.

Protective influence of coded amino acids on the development of liver tissue culture in the presence of cytostatic

An urgent problem is the search for substances that can provide a protective effect in cases of DNA synthesis and repair disorders that arise as a result of side effects of cytostatic drugs used in the treatment of cancer. The aim of this work was to study the effect of 20 encoded amino acids in the presence of Cyclophosphane on the development of organotypic culture of rat liver tissue. The results obtained indicate that Cyclophosphane; which simulates the action of such cytostatic substances; inhibits cell proliferation in the liver tissue. It was also found that the encoded amino acids: asparagine; arginine; and glutamic acid; eliminate the inhibitory effect of Cyclophosphane in liver tissue culture. The growth zone of explants after combined exposure to Cyclophosphane (whose isolated action suppressed the growth zone) and these amino acids increased significantly and reached control values. Thus; the experimental data create the basis for the development of methods for the therapeutic use of the three studied amino acids for the removal of side effects in the treatment with cytostatic drugs.

Features of DNA repair in dermal fibroblasts in ataxia-telangiectasia patients with mosaic type of manifestation of active ATM kinase

Cell mosaicism is found in biological systems much more often than clinically identified forms of the disease, in some cases, "erased forms” or "normal variants” are phenotypic manifestations of mosaicism. Some diseases, difficult for a clinical diagnosis, such as ataxia-telangiectasia, are based on cell mosaicism. This work is aimed to study DNA repair disorders in the cell lines of dermal fibroblasts isolated from skin biopsies of 5 patients with a clinically diagnosed ataxia-telangiectasia. In the obtained cell lines, the method of indirect immunofluorescence was used to determine the number, intensity, focus area pATMSer1981 and 53BP1, as well as the number of cells with the active form of the ATM kinase. The mosaic pattern of malfunctioning of the active form of the ATM kinase, phospho-ATM Ser1981, was revealed at different time intervals after exposure to ionizing radiation at a dose of 2 Gy. Significant differences were found between the number of ATMSer1981 and 53BP1 foci, the fluorescence intensity and their area in the cells of patients with ataxia-telangiectasia and healthy donors. The results of this work can be used in the diagnosis of ataxia-telangiec-tasia and determining the degree of impairment of the functional activity of the ATM gene.

Chromothripsis and DNA Repair Disorders.

Chromothripsis is a mutational mechanism leading to complex and relatively clustered chromosomal rearrangements, resulting in diverse phenotypic outcomes depending on the involved genomic landscapes. It may occur both in the germ and the somatic cells, resulting in congenital and developmental disorders and cancer, respectively. Asymptomatic individuals may be carriers of chromotriptic rearrangements and experience recurrent reproductive failures when two or more chromosomes are involved. Several mechanisms are postulated to underlie chromothripsis. The most attractive hypothesis involves chromosome pulverization in micronuclei, followed by the incorrect reassembly of fragments through DNA repair to explain the clustered nature of the observed complex rearrangements. Moreover, exogenous or endogenous DNA damage induction and dicentric bridge formation may be involved. Chromosome instability is commonly observed in the cells of patients with DNA repair disorders, such as ataxia telangiectasia, Nijmegen breakage syndrome, and Bloom syndrome. In addition, germline variations of TP53 have been associated with chromothripsis in sonic hedgehog medulloblastoma and acute myeloid leukemia. In the present review, we focus on the underlying mechanisms of chromothripsis and the involvement of defective DNA repair genes, resulting in chromosome instability and chromothripsis-like rearrangements.

Early diagnosis of ataxia telangiectasia in the neonatal phase: a parents\u2019 perspective

Ataxia telangiectasia (A-T) is a severe neurodegenerative disorder with variable immunodeficiency. Together with the Dutch A-T community, we investigated the opinion of A-T parents on an early A-T diagnosis in the asymptomatic phase of the disease. During an annual national meeting for A-T patients and families, the topic of an early A-T diagnosis was discussed in relation to the recent introduction of neonatal screening for severe combined immunodeficiency (SCID) in the Netherlands. Based on the discussion, individual arguments were identified and processed into a questionnaire, which was sent out to 64 A-T parents (32 families). Arguments included were insecurity to diagnosis, possible medical advantages, appropriate genetic counseling and family planning, loss of “golden” year(s), and early cancer screening for parents. The response rate was 55% (n = 35 parents). Twenty-six (74%) parents felt that the advantages of an early diagnosis outweighed the disadvantages, five parents thought that the disadvantages would outweigh the advantages (14%), and four parents did not indicate a preference.Conclusion: The majority of parents of a child with A-T would have preferred an early diagnosis during the asymptomatic phase of the disease, because the uncertainty during the diagnostic process had had a major impact on their lives. In addition, the knowledge of being carriers of an ATM gene mutation influenced decisions about family planning. Parents who opposed against an early diagnosis emphasized the joy of having a seemingly healthy child until diagnosis.What is Known:• Ataxia telangiectasia (A-T) is a devastating DNA repair disorder with a huge impact on quality of life of patients and their parents.• Patients with A-T may incidentally be identified at birth as the consequence of neonatal screening for severe combined immunodeficiency (SCID).What is New:• The majority of Dutch parents of A-T patients (74%) would have preferred an early diagnosis of their child in the asymptomatic phase of the disease.• Major arguments for an early A-T diagnosis were (1) the experienced insecurity in diagnostic trajectories and its impact on families and (2) the knowledge of being ATM mutation carriers when deciding about family planning. An argument against an early diagnosis is losing the joy of having a seemingly healthy child until diagnosis.

Dilemma of Reporting Incidental Findings in Newborn Screening Programs for SCID: Parents' Perspective on Ataxia Telangiectasia.

Background: Ataxia Telangiectasia (A-T) is a severe DNA repair disorder that leads to a broad range of symptoms including neurodegeneration and a variable immunodeficiency. A-T is one of the incidental findings that accompanies newborn screening (NBS) for severe combined immunodeficiency (SCID), leading to an early diagnosis of A-T at birth in a pre-symptomatic stage. While some countries embrace all incidental findings, the current policy in the Netherlands on reporting untreatable incidental findings is more conservative. We present parents' perspectives and considerations on the various advantages vs. disadvantages of early and late diagnosis of A-T.Methods: A questionnaire was developed and sent to 4,000 parents of healthy newborns who participated in the Dutch SONNET-study (implementation pilot for newborn screening for SCID). The questionnaire consisted of open-ended and scale questions on advantages and disadvantages of early and late diagnosis of A-T. To address potential bias, demographic characteristics of the study sample were compared to a reference population.Results: A total of 664 of 4,000 parents sent back the questionnaire (response rate 16.6%). The vast majority of parents (81.9%) favored early diagnosis of A-T over late diagnosis. Main arguments were to avoid a long period of uncertainty prior to diagnosis and to ensure the most optimal clinical care and guidance from the onset of symptoms. Parents who favored late diagnosis of A-T stated that early diagnosis would not lead to improved quality of life and preferred to enjoy the asymptomatic “golden years” with their child. The majority of parents (81.1%) stated that they would participate in newborn screening for A-T if a test was available.Conclusions: Reporting untreatable incidental findings remains a disputed topic worldwide. Although the current policy in the Netherlands is not to report untreatable incidental findings, unless the health advantage is clear, the majority of parents of healthy newborns are in favor of an early A-T diagnosis in the pre-symptomatic phase of the disorder. Our results as well as other studies that showed support for the screening of untreatable disorders may serve as valuable tools to inform policymakers in their considerations about NBS for untreatable disorders.

Translational research in disorders of DNA repair: the challenges in the application of therapeutic discoveries to the treatment of human disease.

Translational research in disorders of DNA repair: the challenges in the application of therapeutic discoveries to the treatment of human disease.

Xeroderma Pigmentosum

Xeroderma pigmentosum is a DNA repair disorder characterized by the occurrence of pigmented freckles and skin cancers on sun-exposed areas. Additionally, more than 50% of patients present with progressive degenerative neurological symptoms. Eight clinical subtypes of this condition are known, and neurological symptoms can be seen in XP-A, B, D, F, G complementation groups.

Functional Comparison of XPF Missense Mutations Associated to Multiple DNA Repair Disorders.

XPF endonuclease is one of the most important DNA repair proteins. Encoded by XPF/ERCC4, XPF provides the enzymatic activity of XPF-ERCC1 heterodimer, an endonuclease that incises at the 5’ side of various DNA lesions. XPF is essential for nucleotide excision repair (NER) and interstrand crosslink repair (ICLR). XPF/ERCC4 mutations are associated with several human diseases: Xeroderma Pigmentosum (XP), Segmental Progeria (XFE), Fanconi Anemia (FA), Cockayne Syndrome (CS), and XP/CS combined disease (XPCSCD). Most affected individuals are compound heterozygotes for XPF/ERCC4 mutations complicating the identification of genotype/phenotype correlations. We report a detailed overview of NER and ICLR functional studies in human XPF-KO (knock-out) isogenic cells expressing six disease-specific pathogenic XPF amino acid substitution mutations. Ultraviolet (UV) sensitivity and unscheduled DNA synthesis (UDS) assays provide the most reliable information to discern mutations associated with ICLR impairment from mutations related to NER deficiency, whereas recovery of RNA synthesis (RRS) assays results hint to a possible role of XPF in resolving R-loops. Our functional studies demonstrate that a defined cellular phenotype cannot be easily correlated to each XPF mutation. Substituted positions along XPF sequences are not predictive of cellular phenotype nor reflect a particular disease. Therefore, in addition to mutation type, allelic interactions, protein stability and intracellular distribution of mutant proteins may also contribute to alter DNA repair pathways balance leading to clinically distinct disorders.

Rubella Virus-Associated Cutaneous Granulomatous Disease: a Unique Complication in Immune-Deficient Patients, Not Limited to DNA Repair Disorders.

The association of immunodeficiency-related vaccine-derived rubella virus (iVDRV) with cutaneous and visceral granulomatous disease has been reported in patients with primary immunodeficiency disorders (PIDs). The majority of these PID patients with rubella-positive granulomas had DNA repair disorders. To support this line of inquiry, we provide additional descriptive data on seven previously reported patients with Nijmegen breakage syndrome (NBS) (n = 3) and ataxia telangiectasia (AT) (n = 4) as well as eight previously unreported patients with iVDRV-induced cutaneous granulomas and DNA repair disorders including NBS (n = 1), AT (n = 5), DNA ligase 4 deficiency (n = 1), and Artemis deficiency (n = 1). We also provide descriptive data on several previously unreported PID patients with iVDRV-induced cutaneous granulomas including cartilage hair hypoplasia (n = 1), warts, hypogammaglobulinemia, immunodeficiency, myelokathexis (WHIM) syndrome (n = 1), MHC class II deficiency (n = 1), Coronin-1A deficiency (n = 1), X-linked severe combined immunodeficiency (X-SCID) (n = 1), and combined immunodeficiency without a molecular diagnosis (n = 1). At the time of this report, the median age of the patients with skin granulomas and DNA repair disorders was 9years (range 3-18). Cutaneous granulomas have been documented in all, while visceral granulomas were observed in six cases (40%). All patients had received rubella virus vaccine. The median duration of time elapsed from vaccination to the development of cutaneous granulomas was 48months (range 2-152). Hematopoietic cell transplantation was reported to result in scarring resolution of cutaneous granulomas in two patients with NBS, one patient with AT, one patient with Artemis deficiency, one patient with DNA Ligase 4 deficiency, one patient with MHC class II deficiency, and one patient with combined immunodeficiency without a known molecular etiology. Of the previously reported and unreported cases, the majority share the diagnosis of a DNA repair disorder. Analysis of additional patients with this complication may clarify determinants of rubella pathogenesis, identify specific immune defects resulting in chronic infection, and may lead to defect-specific therapies.

Current Understanding and Future Research Priorities in Malignancy Associated With Inborn Errors of Immunity and DNA Repair Disorders: The Perspective of an Interdisciplinary Working Group.

Patients with inborn errors of immunity or DNA repair defects are at significant risk of developing malignancy and this complication of their underlying condition represents a substantial cause of morbidity and mortality. Whilst this risk is increasingly well-recognized, our understanding of the causative mechanisms remains incomplete. Diagnosing cancer is challenging in the presence of underlying co-morbidities and frequently other inflammatory and lymphoproliferative processes. We lack a structured approach to management despite recognizing the competing challenges of poor response to therapy and increased risk of toxicity. Finally, clinicians need guidance on how to screen for malignancy in many of these predisposing immunodeficiencies. In order to begin to address these challenges, we brought together representatives of European Immunology and Pediatric Haemato-Oncology to define the current state of our knowledge and identify priorities for clinical and research development. We propose key developmental priorities which our two communities will need to work together to address, collaborating with colleagues around the world.

Growth Hormone's Links to Cancer.

Several components of the GH axis are involved in tumor progression, and GH-induced intracellular signaling has been strongly associated with breast cancer susceptibility in genome-wide association studies. In the general population, high IGF-I levels and low IGF-binding protein-3 levels within the normal range are associated with the development of common malignancies, and components of the GH-IGF signaling system exhibit correlations with clinical, histopathological, and therapeutic parameters in cancer patients. Despite promising findings in preclinical studies, anticancer therapies targeting the GH-IGF signaling system have led to disappointing results in clinical trials. There is substantial evidence for some degree of protection against tumor development in several animal models and in patients with genetic defects associated with GH deficiency or resistance. In contrast, the link between GH excess and cancer risk in acromegaly patients is much less clear, and cancer screening in acromegaly has been a highly controversial issue. Recent studies have shown that increased life expectancy in acromegaly patients who attain normal GH and IGF-I levels is associated with more deaths due to age-related cancers. Replacement GH therapy in GH deficiency hypopituitary adults and short children has been shown to be safe when no other risk factors for malignancy are present. Nevertheless, the use of GH in cancer survivors and in short children with RASopathies, chromosomal breakage syndromes, or DNA-repair disorders should be carefully evaluated owing to an increased risk of recurrence, primary cancer, or second neoplasia in these individuals.

Rheumatological manifestations in primary immunodeficiency diseases

Primary immune deficiencies (PIDs) are characterized by quantitative and/or functional abnormalities of the immune system elements. Bone and joint abnormalities are not rare in patients with immunodeficiencies. Joint manifestations, of which arthritis is the most common, occur mainly in humoral PIDs (X-linked agammaglobulinemia, common variable immunodeficiency, and IgA deficiency) and occasionally in defects of the phagocyte system (chronic granulomatous disease, glicogen storage diseases). Monoarthritis or oligoarthritis is the usual pattern, caused by Mycoplasma, Staphylococcus, Streptococcus, Pneumococcus or Haemophilus species. These bacteria can provoke not only synovial infections, but also aseptic arthritogenic inflammatory responses. Infectious arthritis or osteomyelitis must be diagnosed and treated with antimicrobial therapy at the earliest. Bone lesions are far less common and usually present as infectious complications in humoral PID. Larger bone manifestations occur in hyper-IgE syndrome and spondyloepiphyseal dysplasia. Short stature is the most common in reticular dysgenesis, in autoimmune polyendocrinopathy candidiasis ectodermal dysplasia and in DNA repair disorders. Knowledge of PID syndromes both enhances the diagnostic capabilities of physicians and provides understanding the pathophysiology of bone and joint abnormalities associated with immune dysfunction. In children and occasionally in adults, a combination of bone and/or joint manifestations and hypogammaglobulinemia may be the first sign of PID. When lymphoproliferative disease or infection can not be proved, investigations for PID should be accomplished. Orv Hetil. 2018; 159(23): 918-928.