Inborn errors of immunity (IEI), formerly known as primary immunodeficiency disorders (PIDs), are inherited disorders caused by damaging germline variants in single genes, which result in increased susceptibility to infections and in allergic, autoimmune, autoinflammatory, nonmalignant lymphoproliferative, and neoplastic conditions. Along with well-known warning signs of PID, attention should be paid to signs of immune dysregulation, which seem to be equally important to susceptibility to infection in defining IEI. The modern diagnostics of IEI offer a variety of approaches but with some problems. The aim of this review is to discuss the diagnostic challenges in IEI patients in the context of an immune dysregulation background.

Deficits in disorders of humoral immunity associated with a deficit of antibodies are the most common primary immunodeficiency. Total IgG and IgG subclasses measurements are used to diagnose, differentiate and control in patients with primary and secondary immunodeficiencies. The purpose of the study was to analyze the structure patients group according to difference between total IgG and sum of the IgG subclasses and to determine factors affecting the level of this difference. This study was based on data collected from 670 children referred to the Department of Clinical Immunology and Pediatrics in order to diagnose the immune disorders. For all children the level of the total of immunoglobulins IgG and of the IgG subclasses (IgG1, IgG2, IgG3, IgG4) were determined. The group of children was divided into subgroups according to gender, age (under 6 years of age, 6.5–12 years, and 12–18 years), and IgG abnormality (below the normal range, normal and above the normal range). In the patients group, the total IgG values were on average higher than sum of the IgG subclasses. Statistical analysis shown the all parameters under study (age, gender and IgG abnormality) influence statistically significant on the discrepancy between the sum of the IgG subclasses and total IgG. Assessment of IgG and IgG subclasses levels is based on different methods what causes the discrepancy between the sum of the IgG subclasses and total IgG. Standardization in that regard is crucial. In addition, we have shown the reliability of the results obtained. Despite the determination in two different laboratories and on different analyzers, as well as the freezing process does not affect the test results.

Domestic rabbits have teeth that grow throughout the animal’s life and are prone to disease. Clinical signs of dental disease in domestic rabbits are non-specific, and, therefore, a definitive diagnosis usually requires additional methods. This study was carried out on a group of 105 domestic rabbits aged 3 to 9 years. In total, 90 domestic rabbits with dental disease visible on CT images and other secondary diseases of the head area qualified for this study. Malocclusion was found in 57 (63.3%). Retrograde elongation of the tooth apices in the mandible was present in 39 (43.3%), and it was present in the maxilla in 48 (53%). Clinical tooth crowns were overgrown in 39 (43%). Dental abscesses were present in 54 (63%). Secondary to the presence of a dental abscess, osteomyelitis was found in 43 (79% of the animals with a dental abscess). Dental inflammatory resorption was found in 36 (40%). Secondary to dental disease, nasal cavity inflammation was found in 18 (20%). Otitis media was present in six (6.7%). The most common dental disease found in this study’s animals was malocclusion secondary to abnormal clinical crown abrasion and abnormal tooth growth. In domestic rabbits, osteomyelitis is a common complication of dental abscesses. Computed tomography is an invaluable diagnostic method in the diagnosis of dental disease and secondary diseases of the head area, such as inflammation of the nasal cavities or otitis media, in pet rabbits.