Association between Wegener's granulomatosis and increased antithyroid antibodies: report of two cases and review of the literature.

We report two patients with severe manifestations of Wegener's granulomatosis, who also had significantly increased antithyroid antibodies. Auto-immune reaction against various human tissue antigens probably explains the association between increased anti-neutrophil cytoplasmic and antithyroid antibodies. The clinicians should include thyroid function and antithyroid antibody tests in the laboratory work up of the patients with Wegener's granulomatosis.

Recurrent omphalitis in adults.

Recurrent omphalitis is seen more frequently in children, but clinicians world-wide are occasionally challenged by cases of recurrent omphalitis in adults. Apart from folliculitis and infections associated with pilonidal cysts and piercing of the umbilical area, the clinician should consider the possibility of infected remnants of the allantois or the omphalomesenteric (vitelline) duct in adult patients with recurrent omphalitis. Imaging tests such as ultrasound and computed tomography scan frequently help to identify the exact cause of recurrent omphalitis. The combined surgical and medical management usually leads to cure of the problem.

Munchausen's syndrome presenting as severe panniculitis.

Factitious disorders may trouble any physician during his/her career. A considerable number of cases of Munchausen's syndrome (self-induced disorder) are misdiagnosed in clinical practice. A 36-year-old woman was admitted to our hospital because of fever and abdominal pain. Physical examination showed signs of inflammation of the abdominal wall, and histological examination revealed severe panniculitis. We investigated various aetiologic factors that could probably be related to fat necrosis, but we found no explanation of the phenomenon until we verified the diagnosis of Munchausen's syndrome. 2 years later, the patient underwent surgery for removal of needles, which she herself had deliberately located under her skin. High index of suspicion and physician's persistence are necessary to make the correct diagnosis in the various protean manifestations of Munchausen's syndrome.

MHC class II Ab diabetogenic residue 57 Asp/non-Asp dimorphism influences T-cell recognition and selection.

Human and mouse major histocompatibility complex class II beta chain alleles associated with predisposition to type I diabetes often encode a non-charged residue at position 57 rather than the negatively charged aspartate residue characteristic of non-susceptible haplotypes. The mechanism(s) whereby this polymorphism promotes eventual pancreatic beta cell destruction is unclear. The type I diabetes-susceptible mouse strain NOD (H2(g7)) encodes serine at Ab position 57 and is one of the few mouse class II molecules not encoding aspartate at this position. To gain insight into the structural impact of this amino acid substitution and any influence it may have on T-cell selection, we assessed whether T-cell repertoires selected by diabetogenic class II (Ag7) are tolerant of mutant Ab (residues 56 and 57) H2-Ag7. We find that NOD mice mount an allogeneic response to skin grafts expressing mutant position 57 (serine to aspartate) Abg7; but not to grafts expressing mutant position 56 (histidine to proline) Abg7. Graft rejection correlates with the presence of CD4(+) T cells specific for the mutant H2-Ag7 heterodimer. Genetic analyses are consistent with Ab position 57 aspartate/non-aspartate dimorphism influencing peptide selection and hence repertoire selection. Direct evidence for the serine to aspartate substitution at position 57 influencing T-cell selection is found by analysis of peripheral T-cell receptor (TCR) usage and the CD4/CD8 T-cell ratio.