A porcine model of acute, haematogenous, localized osteomyelitis due to Staphylococcus aureus: a pathomorphological study

A porcine model of acute, haematogenous, localized osteomyelitis was established. Serial dilutions of Staphylococcus aureus [5-50-500-5000-50 000 CFU/kg body weight (BW) suspended in saline or saline alone] were inoculated into the right brachial artery of pigs (BW 15 kg) separated into six groups of two animals. During the infection, blood was collected for cultivation, and after the animals were killed from day 5 to 15, they were necropsied and tissues were sampled for histopathology. Animals receiving ≤500 CFU/kg BW were free of lesions. Pigs inoculated with 5000 and 50 000 CFU/kg BW only developed microabscesses in bones of the infected legs. In the centre of microabscesses, S. aureus was regularly demonstrated together with necrotic neutrophils. Often, bone lesions resulted in trabecular osteonecrosis. The present localized model of acute haematogenous osteomyelitis revealed a pattern of development and presence of lesions similar to the situation in children. Therefore, this model should be reliably applied in studies of this disease with respect to e.g. pathophysiology and pathomorphology. Moreover, because of the regional containment of the infection to a defined number of bones, the model should be applicable also for screening of new therapy strategies.     

Efficacy of ivermectin and oxfendazole against Taenia solium cysticercosis and other parasitoses in naturally infected pigs

Smallholder semi-confined pig production is a fast growing practice in sub-Saharan Africa with an unfortunate outcome of high prevalence of Taenia solium cysticercosis and other parasitoses. The widely used anthelmintic for control of endo and ecto-parasites in pigs in the area is ivermectin at a recommended dose of 0.3 mg/kg. This study was conducted to evaluate the efficacy and safety in pigs after subcutaneous injection of ivermectin (IVM, 0.3 mg/kg) and orally administration of oxfendazole (OFZ, 30 mg/kg) in treatment of porcine cysticercosis and other parasitoses in naturally infected pigs. A total of 61 pigs with T. solium cysticercosis (38 males and 23 females) as identified by tongue palpation with age ranging from 3 to 24 months were recruited. The pigs were stratified based on sex, age and number of cysts on the tongue and randomly allocated to IVM, OFZ and control groups. Three days before treatment and two weeks after treatment faecal samples and skin scrapings were taken to establish the burden of endo- and ectoparasites, respectively and the effect of the treatment. No adverse effect was observed in any of the treatment groups throughout the study period. Half of the pigs from each group were slaughtered at week four and the remaining half at week twelve post treatment. The IVM treatment group had no significant effect (p = 0.224) on T. solium cysts viability in comparison to the control group. Significant effect on cysts viability was observed in the OFZ treated group (p < 0.001) compared to IVM and control groups in all muscle tissues. Regarding to brain cysts, neither of the drugs was efficacious. Ivermectin and OFZ treatments significantly reduced (p < 0.001) the faecal egg count of Ascaris suum, strongyles and Trichuris suis two weeks after treatment. At slaughter, Oesophagostomum dentatum, Ascarops strongylina and Physocephalus sexalatus were recovered from pigs in the IVM treated and in the control groups. Ivermectin was 100% effective in control of Sarcoptes scabiei. In conclusion, IVM at a single dose of 0.3 mg/kg was efficacious against ectoparasites but did not effectively cure pigs from T. solium cysticercosis or nematodes. Oxfendazole, on the other hand, killed all nematodes and muscle cysts, but did not have any effect on ectoparasites. A combination of the two drugs would be a most useful treatment option for control of pig parasitoses in sub-Saharan Africa.     

Recurrent arthritis as presenting symptom of osteomyelitis

We present a patient who had one episode of prepatellar bursitis and subsequently several episodes of arthritis of his right knee. Cultures of several punctures of his knee remained sterile, but the patient had been taking oral antibiotics on each of these occasions against our medical advice. Ultimately a diagnostic puncture revealed growth of Staphylococcus aureus. An X-ray demonstrated an osteolytic lesion of the patella, but no defect in the articular surface of the patella could be visualised. MRI demonstrated a communication between the osteomyelitic focus through the medial retinaculum to the bursa suprapatellaris and the knee joint. Osteomyelitis of the patella is mainly a disease of childhood. This case is, to our knowledge, the first report on the association between bursitis, osteomyelitis of the patella and recurrent septic arthritis of the knee in an adult. The literature is reviewed and discussed briefly.     

The beta-globin gene on the Chinese delta beta-thalassemia chromosome carries a promoter mutation

A new type of delta beta-thalassemia characterized by decreased expression of the beta-globin gene and increased expression of both G gamma and A gamma globin gene in the absence of a detectable deletion has recently been described in the Chinese population. In this study we characterize the mutant beta-globin gene from this delta beta- thalassemia chromosome. An A to G transversion is identified in the "ATA" sequence of the promoter region that leads to decreased expression of the beta-globin gene in vivo and in vitro. We also demonstrate the presence of this mutation in every individual with a high fetal hemoglobin phenotype in this family and its absence in every individual with a normal hemoglobin phenotype. This same promoter mutation has recently been detected in Chinese beta-thalassemia genes where it is present on chromosomes of the same haplotype as that of the delta beta-thalassemia chromosome we are studying. These data support the hypothesis that an as yet unidentified mutation occurred on the ancestral chromosome carrying the promoter mutation and subsequently gave rise to the delta beta-thalassemia phenotype.     

Risk and significance of endoscopic/radiological evidence of recurrent Crohn's disease

BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7)     

Myelomonocytic antigen positive multiple myeloma

In a four year span, between 1983 and 1987, 215 bone marrow and cell culture samples from 125 myeloma patients were immunotyped and coexpression of myelomonocytic and plasma cell antigens occurred in 16 (13%). We employed both immunohistochemical and flow cytometry methods including coplots and double labelling. Three types of myeloma cases were found: (1) those with isolated myeloid antigen coexpression, usually Leu M1 or esterase (BE, CE) positive (11 cases); (2) those with multiple myeloid antigens (Leu M1, M3, M5, MY7, BE, CE) (four cases); and (3) one case beginning as 1 and ending as 2. Isolated myeloid antigen expression was generally associated with typical features of myeloma with survival close to the anticipated median (33 months), while multiple myeloid antigen expression was associated with more aggressive disease and shorter survival duration (median survival 16 months). The latter subgroup also had other poor prognostic factors including high labelling index and common acute lymphoblastic leukemia antigen (CALLA) positivity. Other features found overall were frequent abnormal karyotypes (seven of 12 abnormal) and coexpressed IgA (eight of 16); all IgA+ cases also coexpressed Leu M1. We conclude that there is an unusual and unexpected predilection for coexpression of myelomonocytic antigens in myeloma cells. The reasons are not immediately obvious. Whether the coexpression indicates that myeloma cells truly have latent multilineage potential or just aberrantly coexpress other hematopoietic antigens as a manifestation of malignancy remains to be explained. However, a cell line established from the bone marrow of one patient is a valuable scientific tool allowing detailed analysis of these questions.     

Beta-thalassemia due to two novel nucleotide substitutions in consensus acceptor splice sequences of the beta-globin gene

We have identified two novel RNA-splicing mutations affecting a critical nucleotide (nt) in the acceptor consensus sequences at both the IVS-1/exon 2 and IVS-2/exon 3 junctions of the human beta-globin gene. Both mutations are single nt substitutions, T to G and C to A, at position -3 adjacent to the invariant AG dinucleotide. For the IVS- 2/exon 3 mutation abnormal splicing into the cryptic splice site at IVS- 2 nt 579 is documented. Identification of these two mutations provides further support for the importance of the location of specific nucleotides within the consensus sequences in splice site selection and RNA processing.