Nodular hepatic lesions secondary to myeloma IgA presenting as fever of unknown origin

A 45 year old male presented with IgA multiple myeloma s/p (status post) autologous hematopoietic stem cell transplantation; and with a history of six weeks of fever and constitutional symptoms. Liver tests showed an infiltrative pattern, with ultrasound evidence of multiple nodular lesions. A laparoscopic biopsy identified circumscribed myeloma foci. This is the first reported case of myeloma nodular liver lesions causing a fever of unknown origin.     

Deposition of amyloid of unknown origin in articular cartilage.

Articular cartilage, obtained from the large toe during hallux valgus operations in 37 patients, was investigated for the presence of amyloid by using the Congo red staining method. Amyloid deposits were demonstrated, particularly in the superficial layer of the cartilage, in 30 cases. This amyloid did not react immunohistochemically with any of the antibodies against the known five major amyloid types (AA, A lambda, A kappa, AF, AB). From these data it is concluded that hyaline cartilage in older individuals is prone to infiltration by an amyloid of a hitherto unidentified class. From the morphological observations there seems to be no correlation between amyloid deposits and the development of osteoarthrosis.     

Brain Ia antigens have a bone marrow origin

Our results, using radiation-induced bone marrow chimeras, demonstrate that the Ia antigen found in the brains of such animals is produced by cells having precursors in the bone marrow. These cells are not immediately blood borne since no IgM is detected in these brains. This rules out the obvious possibility of B-lymphocyte contamination as the source of Ia in the brain cell preparations. It thus appears that the central nervous system, like many other nonlymphoid organs, has a source of Ia-positive cells that are derived from bone marrow precursors.     

Non-African populations of Drosophila melanogaster have a unique origin

Drosophila melanogaster is widely used as a model in DNA variation studies. Patterns of polymorphism have, however, been affected by the history of this species, which is thought to have recently spread out of Africa to the rest of the world. We analyzed DNA sequence variation in 11 populations, including four continental African and seven non-African samples (including Madagascar), at four independent X-linked loci. Variation patterns at all four loci followed neutral expectations in all African populations, but departed from it in all non-African ones due to a marked haplotype dimorphism at three out of four loci. We also found that all non-African populations show the same major haplotypes, though in various frequencies. A parsimonious explanation for these observations is that all non-African populations are derived from a single ancestral population having undergone a substantial reduction of polymorphism, probably through a bottleneck. Less likely alternatives involve either selection at all four loci simultaneously (including balancing selection at three of them), or admixture between two divergent populations. Small but significant structure was observed among African populations, and there were indications of differentiation across Eurasia for non-African ones. Since population history may result in non-equilibrium variation patterns, our study confirms that the search for footprints of selection in the D. melanogaster genome must include a sufficient understanding of its history.     

Ceasing of epithelisation and deposit formation of unknown origin on the cornea.

The author presents a so far unknown pathological process interrupting permanently the regeneration of the superficially damaged cornea, and its consequences and therapy of the condition as well. The process occurs only in 5.6% of the injured individuals. The occurrence is in no correlation with the quality or extent of the damage. Also it is independent of the form and duration of therapy. The essence of the pathological changes is the slowing of corneal epithelisation within 2-4 days, followed by a complete cessation. After that a thin membrane-like layer develops simultaneously and evenly within 12 days on the area without epithelium, the surface of which is dull, transparent and whitish in colour. Within weeks or months an individually varying thickening of the membrane occurs, but the area does not grow. The surface becomes whitish-grey and is without any epithelium and with no adherence to tear. The deposits are closely and inseparably adherent to their base, their substance is rigid, being brittle only at the margins. The lesion is staining greenish-yellow with Na-fluorescein, and lively blue with toluidine blue. It is staining in small reddish-brown with rose bengal. In vivo the deposits are not measurably influenced by hyaluronidase, trypsin, alpha-chymotrypsin and papain. The microbes play no role in the process. Histological and electron-microscopical examinations suggest the corneal deposit are the product of the necrobiotic process occurring on the corneal surface during regeneration. The specific treatment consists of local application of corticoid-heparin. On the basis of the results of the examinations and literary data the author suggests that the corneal deposition and the similarly rare KCV (keratoconjunctivitis vernalis) plaque formation is the same specific process, i.e. the peculiar manifestation of the atopic state of the organism occurring independently of age.     

FDG-PET-CT in pyrexia of unknown origin and inflammatory diseases

FDG-PET has been used successfully over the last decade for imaging patients with fever of unknown origin. Nowadays, PET-CT has become the standard in many centres although a limited number of prospective studies is available. This article summarizes the experience in the field and the potential use of FDG-PET in other inflammatory or immune diseases, such as sarcoidosis or rheumatoid arthritis.