Electrophysiological recordings during the peripheral nerve evaluation (PNE) test in complete spinal cord injury patients

Up until now, the exact mechanism by which neuromodulation using sacral nerve stimulation works still remains unknown. Recent studies of pelvic floor contraction during peripheral nerve evaluation (PNE) have shown that several muscle responses are reflexly mediated. However, whether these reflexes originate from a segmental level within the sacral spinal cord or from supraspinal neuronal centers involving spino-bulbospinal pathways remains to be determined. Therefore, recordings of external anal sphincter reflexes during PNE in complete spinal cord injury (SCI) patients was performed. Three patients with complete SCI (two female and one male) suffering from neurogenic incontinence underwent the first stage of a stimulator implant (peripheral nerve evaluation). Stimulation was obtained through an electrode placed in the S3 foramen. Concomitantly, the latency of the response of the striated anal sphincter was measured using a concentric needle electrode placed in the striated part of the anal sphincter. Repeated measurements within an interval of 30 min were performed to confirm the reliability of the responses. In all subjects, reflex responses of early and late latencies could be recorded. The early response showed a mean latency of 41.2 ms (range 33.3-62 ms), which corresponds to a segmental reflex, similar to the pudendo-anal reflex. The late response appeared with a mean latency of 189.4 ms (range: 183.3-197.8 ms) and with high variability and fatigability, suggesting a reflex response organized at polysegmental spinal levels. Despite successful foramina lead placement, none of our complete SCI patients showed any improvement of neurogenic incontinence after 5 days of treatment by sacral nerve stimulation. The findings confirm that the anal contractions observed during peripheral nerve evaluation are reflex responses mediated by afferent pathways. Both the early and late reflex responses are of spinal origin, since they were obtained in complete SCI patients in whom all spino-bulbo spinal loops are supposed to be interrupted. The finding that neuromodulation is working in non-neurogenic patients but is less successful in complete SCI patients could give evidence that preserved spino-bulbo spinal loops contribute to the positive effects of neuromodulation. The role of an eventual spino-bulbo spinal loop acting during neuromodulation in non-neurogenic patients has to be assessed in further studies.

Bladder outflow obstruction caused by prostate metastasis in a young male

A 38-year-old male patient presented with symptoms of bladder outflow obstruction. Rectal palpation revealed a giant prostate. Sonography only confirmed the enlarged prostate. Magnetic resonance imaging showed, on both T1- and T2-weighted sequences, a large, inhomogenously hypointense, encapsulated prostate tumor encompassing the entire prostate. No capsular penetration or seminal vesicle invasion was seen. Transurethral biopsy of the prostate was performed. Histology demonstrated a prostate metastasis of colorectal carcinoma.

Prevalence of Helicobacter pylori and hepatitis C virus infections among non-Hodgkin's lymphoma patients in Southern Switzerland

BACKGROUND AND OBJECTIVE

Several recent studies have reported a high rate of previous hepatitis C virus (HCV) infection in patients with non-Hodgkin's lymphoma (NHL). However, it appears that there are marked geographical differences in the prevalence of HCV among NHL patients. There is further controversy concerning a possible pathogenetic link between HCV and certain histologic lymphoma subtypes, in particular MALT lymphomas, and it has recently been speculated that HCV might be involved in the multistep process of gastric lymphoma genesis, in addition to the well established role of chronic Helicobacter pylori infection. The aim of this study was to investigate the prevalence of HCV and H. pylori infections in patients with B-cell NHL in Southern Switzerland.

DESIGN AND METHODS

One hundred and eighty newly diagnosed HIV-negative B-cell NHL patients, consecutively seen at a referral oncology center in Southern Switzerland between 1990 and 1995 were prospectively studied. A microparticle enzyme immunoassay was used to detect antibodies to HCV. Serologic determination of HCV genotype was done by the Murex method. The quantitative detection of IgG anti-H. pylori was performed by the Biorad GAP test.

RESULTS

Infection with HCV was detected in 17/180 patients (9.4%; 95% C.I., 6%-15%). This prevalence is significantly higher than that observed in a large survey of 5424 new blood donors from the same area tested in 1992-97 (0.9%; 95% C.I., 0.7-1.2). Neither histologic subtypes nor specific extranodal presentations of NHL were associated with a higher prevalence of HCV. HCV serotype 2 (corresponding to genotypes 2a-c) was the most common. HCV infection was significantly associated with a shorter progression-free survival at both univariate and multivariate analysis. Anti-Helicobacter antibodies were detected in 81/180 patients (45%; 95% C.I., 38%-53%) and H. pylori infection was significantly associated with the development of primary lymphomas of the stomach.

INTERPRETATION AND CONCLUSIONS

A high prevalence of HCV infection was detected in NHL lymphoma patients and was associated with a shorter time to lymphoma progression. HCV infection was not correlated with primary gastric presentation or with MALT-type histology. Our findings further support the key role of H.pylori infection in the pathogenesis of primary gastric lymphoma of MALT-type. The possible role of HCV in the pathogenesis of NHL should be further investigated.

[Primary cysts of the spleen: apropos 3 cases with a review of the literature]

The splenic cyst occurs rarely, is benign and often asymptomatic. Surgery is the therapy of choice as soon as the size reaches 2 centimeters. Following the exclusion of an echinococcus infection, the cyst can be treated either by complete resection or by fenestration. Recently laparoscopy has been demonstrated to be a useful alternative to open surgery in the treatment of selected splenic cysts. We report 3 cases successfully operated with conventional surgical procedures and, based on the literature, we review the history, the physical signs, the investigations and the surgical procedures.

[Distal perforation of the small intestine by PEG endpiece in an inguinal hernia patient]

The PEG-ileus is a complication of the intestinal migration of the "bumper". The resulting obstruction or perforation is usually located in the ileum. Patients with hernias, who have a possible or known intrinsic or extrinsic stenosis or who have been X-rayed in the area of the small pelvis, are not suitable for the application of Korula's "migration"-technique with the scheduled intestinal elimination of the "bumper". "Bumpers" that are allowed to remain in the stomach for a long time lose their elasticity and frequently cause a PEG-ileus. When choosing the type of gastrostomy, we should consider which technique could be used in the case of a change or a removal of the material.

The "n-1" model for myelodysplastic syndromes

Current models of leukaemogenesis tend to visualize this process as consisting of several discrete steps. Since myelodysplastic syndromes (MDS) are, almost by definition, pre-leukaemic disorders, we expect that bone marrow from patients with MDS must contain cells which are one step short of full leukaemic transformation: we designate these cells, for convenience, as "n-1". It should be possible therefore to obtain leukaemic transformation in vitro by introducing into n-1 cells a gene with an appropriate leukaemogenic mutation. We have found, by using as a model system the retrovirus VSN-2 (which carries the neomycin-phosphotransferase gene, neo, which confers resistance to the antibiotic G418), that human bone marrow cells can be successfully transfected in microcultures. Indeed, G418-resistant CFU-CM have been recovered from these cultures for a period of several weeks.

Interleukin 1 has positive and negative regulatory effects in human long-term bone marrow culture

The observations that interleukin 1 (IL-1) increases the production of colony-stimulating factors (CSFs) by stromal cells and acts in synergy with those CSFs to stimulate the growth of progenitor cells suggest that IL-1 may have an important role in stimulating hemopoiesis. However, IL-1 also induces the synthesis by stromal cells of inhibitors of hemopoiesis including tumor necrosis factor (TNF) and prostaglandin E2. We have used long-term bone marrow culture (LTBMC) to study the effect of IL-1 on hemopoiesis in the presence of a stromal cell layer. The addition of recombinant (r)IL-1 (10 U/ml) at the initiation of the LTBMC and at each weekly feed resulted in a significant stimulation of nonadherent granulocyte-macrophage colony-forming units (CFU-GM) by week 1 and a sustained increase in colony-stimulating activity (CSA) in culture supernatants. The increased CSA activity was mainly due to granulocyte colony-stimulating factor (G-CSF) as studied by the effects of neutralizing antibodies. Following this initial stimulation, however, nonadherent layer CFU-GM became significantly suppressed by week 4, and the number of nonadherent cells was also reduced. This delayed suppression of hemopoiesis induced by continuous exposure to rIL-1 was partially abrogated by the addition of indomethacin (10(-6) M) to the cultures, but anti-TNF had no such effect and we could not detect significant TNF levels either in culture supernatants or in stromal cell extracts. Our data suggest that prostaglandin inhibitors suppress the negative feedback control of myelopoiesis induced by IL-1 and therefore may have a role in augmenting IL-1 stimulation of myelopoiesis.

Endogenous interleukin-1 can regulate the autonomous growth of the blast cells of acute myeloblastic leukemia by inducing autocrine secretion of GM-CSF

We have studied peripheral blood blast cells from a patient with acute myeloblastic leukemia (AML) whose cells proliferated autonomously at high cell density, but only in the presence of adherent cells. At low cell density in suspension culture and in a clonogenic assay, blast cell growth was stimulated by recombinant granulocyte macrophage colony stimulating factor (GM-CSF) and recombinant interleukin-1 (IL-1) independently. The response to rIL-1 was inhibited (less than 90%) by anti-GM-CSF, suggesting that the proliferative response to IL-1 was mediated by GM-CSF. This was supported by experiments which demonstrated that blast cell conditioned medium prepared in the presence of IL-1 contained GM-CSF activity which stimulated the growth of normal granulocyte-macrophage precursors (CFU-GM) and of homologous GM-CSF responsive AML blasts. As IL-1 but no GM-CSF activity was detected in BCCM prepared without exogenous IL-1 and a neutralizing antibody to IL-1 inhibited the autonomous growth of blasts in suspension culture, we conclude that the endogenous secretion of IL-1 by leukemic cells stimulated autocrine GM-CSF secretion, inducing autonomous growth of the blast cell population.