[Diseases of the cervical lymph nodes in childhood]. / Erkrankungen der Halslymphknoten im Kindesalter.

The lymph nodes are an essential part of the body's immune system and as such are affected in many infectious, autoimmune, metabolic and malignant diseases. The cervical lymph nodes are particularly important because they are the first drainage stations for key points of contact with the outside world (mouth/throat/nose/eyes/ears/respiratory system) - a critical aspect especially among children - and can represent an early clinical sign in their exposed position on a child's slim neck. Involvement of the lymph nodes in multiple conditions is accompanied by a correspondingly large number of available diagnostic procedures. In the interests of time, patient wellbeing and cost, a careful choice of these must be made to permit appropriate treatment. The basis of diagnostic decisions is a detailed anamnesis and clinical examination. Sonography also plays an important role in differential diagnosis of lymph node swelling in children and is useful in answering one of the critical diagnostic questions: is there a suspicion of malignancy? If so, full dissection of the most conspicuous lymph node may be necessary to obtain histological confirmation. Diagnosis and treatment of childhood cervical lymph node disorders present the attending pediatric and ENT physicians with some particular challenges. The spectrum of differential diagnoses and the varying degrees of clinical relevance - from banal infections to malignant diseases - demand a clear and considered approach to the child's individual clinical presentation. Such an approach is described in the following paper.

Comparison of the effects of semi-occlusive polyurethane dressings and hydrocolloid dressings on dermal repair: 1. Cellular changes.

The effects on dermal repair of two wound dressings, one the semi-occlusive polyurethane sheet Opsite, the other the hydrocolloid Granuflex, were compared in full-thickness excised lesions on porcine skin during the period from 5 d to 6 months after injury. Quantitative studies were made of changes in the populations of polymorphonuclear leucocytes, macrophages, fibroblasts, and endothelial cells. The progress of repair in the wounds covered with the semi-occlusive dressing showed a decrease in the number of inflammatory cells (polymorphonuclear leukocytes and macrophages) from 5 to 60 d, whereas the number of proliferative phase cells (fibroblasts and endothelial cells) increased from 5 to 7 d. The total cellularity per unit area showed an increase between 5 and 7 d, that is, during the proliferative phase of repair, and then progressively decreased as the proliferative phase was succeeded by the remodeling phase. In contrast, the repair process in the hydrocolloid-dressed wounds was more complex. The number of inflammatory cells remained relatively high throughout and there were consistently fewer endothelial cells present throughout. Fibroblast number showed an initial fall from 5 to 14 d but then started to increase in number from 21 to 60 d. This chronic inflammatory reaction appeared to be in response to particulate matter that had been incorporated into the wound bed and hypodermis, and was still apparent 6 months after injury, when hydrocolloid particles were detectable microscopically in the hypodermis.

Bone metastasis with superimposed osteomyelitis in prostate cancer.

The following case of a male patient with a history of prostate cancer suffering from pain and swelling in the right mandibular area illustrates the well-known diagnostic problem of a superinfected tumor. Orthopan tomography and CT showed no defects in bone structure or smooth tissue. Whole-body bone scanning showed increased tracer uptake in the mandibular bone and in several other locations in the skeletal system. Antigranulocyte immunoscintigraphy showed increased uptake over the right mandible, whereas the other metastatic sites were visualized as cold spots. A second CT scan depicted a sclerotic lesion with surrounding periostal reaction and soft-tissue swelling and was interpreted as osteomyelitis. Therefore, clinical symptoms, bone scanning, antigranulocyte immunoscintigraphy and follow-up CT resulted in a diagnosis of osteomyelitis, although open needle biopsy revealed the lesion to be prostate cancer metastasis with massive leukocytic invasion.

Utility of technetium-99m-sestamibi to assess osseous tumor spread.

We report the staging results and the surgical outcome of a male patient with squamous-cell carcinoma in the floor of the mouth and a bone SPECT scan suggestive of local tumor infiltration of the mandible. Additional 99mTc-sestamibi SPECT imaging of the primary tumor and superimposing of both studies excluded osseous tumor spread and less extensive surgery was performed. Pathohistological examination confirmed the scintigraphic results and indicated a nonspecific periostal reaction as the cause of the positive bone scan. Nevertheless, a high-resolution camera and careful superimposition of both studies is mandatory if the differential diagnosis of an osseous tumor spread of a malignant tumor in the floor of the mouth and possibly less extensive surgery is at stake.

Infective endocarditis. Current recommendations for prophylaxis.

Antibiotic prophylaxis is indicated for any patient with a predisposing cardiac lesion who undergoes a procedure likely to produce bacteraemia with an organism having the propensity to cause bacterial endocarditis. Cardiac abnormalities have been ranked according to their approximate risk and it is known that the organisms most likely to cause endocarditis are viridans streptococci, Group D streptococci and staphylococci. The procedures likely to induce bacteraemia with each of these are, respectively, dental and upper respiratory with bleeding, urinary and gastrointestinal, and cardiac valve surgery. Antibiotic prophylaxis is impractical when bacteraemia cannot be anticipated and is unnecessary when it is due to organisms such as anaerobes and Gram-negative bacilli which rarely colonise the endocardium. A variety of prophylactic antibiotic regimens, directed against the common aetiological organisms, have been evaluated in animal models of infective endocarditis and it is on the basis of this kind of indirect evidence that several expert committees have made and regularly update their recommendations. Because infective endocarditis is an uncommon disease, a controlled clinical trial to prove the efficacy of prophylaxis would require the enrolment of a prohibitive number of patients. Consequently, there is room for differences of opinion over what constitutes optimum prophylaxis in any particular situation. This review examines the rationale for prophylaxis and compares and contrasts several authoritative recommendations, among which the trend in recent years has been towards simpler oral regimens.

Is early sestamibi imaging in head and neck cancer affected by MDR status, p53 expression, or cell proliferation?

A consensus has emerged that early imaging (within 20 min post-injection [p.i.] of sestamibi) has the highest diagnostic yield. Tc-99m-sestamibi uptake has been associated with P-glycoprotein-mediated multi-drug resistance (MDR), tumor vascularization, invasiveness, and cell proliferation. The aim of this study was to assess whether these parameters affect tumor uptake in current imaging protocols. Twenty-three patients with squamous cell carcinoma (SCC) of the mouth floor who were scheduled for surgery were imaged 5 min. p.i. with a triple-head gamma camera (360 degrees, 3 degrees/step SPECT, UHRPAR collimators). Tumor:nontumor tissue (TBR), tumor:gingiva (TGR), tumor:salivary gland (TSR), and tumor:nuchal muscle ratios (TNR) were calculated based on the cts/pix values of ROIs in the axial slices. The expression of the MDR gene was determined histochemically from biopsies. Cell proliferation was quantitated by the histochemical analysis of the Ki-67 protein (Ki-67 index); additionally, the p53 tumor suppressor gene (p53 index), a posttranslational stabilizer of the cell cycle at the G1 stage, was assessed. No significant differences were found for the uptake indices between MDR+ and MDR- tumors. Moreover, no significant correlation between sestamibi uptake and the Ki-67 and p53 indices could be demonstrated. The diagnostic information content of currently applied imaging protocols for sestamibi in SCC of the mouth floor is not affected by tumor-specific properties.

Evidence for the involvement of the hydroxyl radical in the pathogenesis of excessive connective tissue proliferation in patients with tumor-endoprostheses.

Extensive proliferation of connective tissue around Vitallium implants can be observed in young patients who had limb salvage for primary malignant bone tumors. The underlying mechanism of excess proliferation and collagen accumulation is not known. We were therefore interested to show whether the alloy of the implant induced proliferation of fibroblasts in vitro, acted by a cytotoxic mechanism or generated free radical cross linking of collagen with subsequent accumulation. In vitro tests for proliferation and cytotoxicity using the implant material which consists of a series of transition metals, ruled out a proliferation-inducing or cytotoxic effect of the implant. Determination of ortho-tyrosine (OT), a marker for hydroxyl radical attack on phenylalanine, in the proliferating tissues surrounding the implants revealed significantly higher aromatic hydroxylation in the vitallium surrounding tissue correlating with tissue collagen content (r = 0.86, p < 0.01). Based upon the findings of increased OT and the presence of higher molecular weight bands on SDS-PAGE, representing more cross linked collagen, we suggest that hydroxyl radical attack lead to free radical mediated cross linking of collagen with subsequent collagen accumulation, as collagen cross-linked to a higher degree is less susceptible to proteolytic degradation.The hydroxyl radical attack seems to having been generated by the many transitional metals of the vitallium-alloy.

Determination of bone and tissue concentrations of teicoplanin mixed with hydroxyapatite cement to repair cortical defects.

A highly specific and sensitive isocratic reversed-phase high performance liquid chromatography (HPLC) method for the determination of the major component of teicoplanin in tissue is reported. Comparing fluorescamine and o-phthalaldehyde (OPA) as derivatizing agents, the derivative formed with the latter exhibits superior fluorescence intensity allowing detection of femtomole quantities. Pretreatment for tissue samples is by solid-phase extraction which uses Bakerbond PolarP C(18) cartridges and gives effective clean up from endogenous by-products. Linearity was given from 0.6 to 100 ng per injection. The coefficient of variation did not exceed 5.8% for both interday and intraday assays. It was found that when bone defects are repaired with a hydroxyapatite-teicoplanin mixture, the antibiotic does not degrade, even when it is in the cement for several months. The stability of teicoplanin in bone cement was determined fluorodensitometrically.

Preservation of residual renal function in dialysis patients: effects of dialysis-technique-related factors.

OBJECTIVES: Residual renal function (RRF) is of paramount importance to dialysis adequacy, morbidity, and mortality, particularly for long-term continuous ambulatory peritoneal dialysis (CAPD) patients. Residual renal function seems to be better preserved in patients on CAPD than in hemodialysis (HD) patients. We analyzed RRF in 45 patients with end-stage renal disease (ESRD), commencing either CAPD or HD, to prospectively define the time course of the decline in RRF, and to evaluate dialysis-technique-related factors such as cardiovascular stability and bioincompatibility. STUDY DESIGN: Single-center prospective investigation in parallel design with matched pairs. MATERIALS: Fifteen patients starting CAPD and 15 matched pairs of patients commencing HD were matched according to cause of renal failure and RRF. Hemodialysis patients were assigned to two dialyzer membranes differing markedly in their potential to activate complement and cells (bioincompatibility). Fifteen patients were treated exclusively with the cuprophane membrane (bioincompatible) and the other 15 patients received HD with the high-flux polysulfone membrane (biocompatible). MEASUREMENTS: Residual renal function was determined at initiation of dialytic therapy and after 6, 12, and 24 months. Dry weight (by chest x ray and diameter of the vena cava) was closely recorded throughout the study, and the number of hypotensive episodes counted. RESULTS: Residual renal function declined in both CAPD and HD patients, although this decline was faster in HD patients (2.8 mL/minute after 6 months and 3.7 mL/min after 12 months) than in CAPD patients (0.6 mL/min and 1.4 mL/min after 6 and 12 months respectively). It declined faster in patients with bioincompatible than with biocompatible HD membranes (3.6 mL/min vs 1.9 mL/min after 6 months). Eleven percent of the HD sessions were complicated by clinically relevant blood pressure reductions, but there were no differences between the two dialyzer membrane groups. None of the CAPD patients had documented hypotensive episodes. None of the study patients suffered severe illness or received nephrotoxic antibiotics or radiocontrast media. CONCLUSIONS: The better preservation of RRF in stable CAPD patients corresponded with greater cardiovascular stability compared to HD patients, independently of the membrane used. Furthermore, there was a significantly higher preservation of RRF in HD patients on polysulfone versus cuprophane membranes, indicating an additional effect of biocompatibility, such as less generation of nephrotoxic substances by the membrane. Thus, starting ESRD patients on HD prior to elective CAPD should be avoided for better preservation of RRF.

Cartilaginous exostoses of the mandible.

Although cartilaginous exostosis is considered to be the most common tumor of the skeleton, it is relatively uncommon in the jaws. The pathogenesis of the lesion is unclear. Three cases are presented and the development of the tumors from embryonic cartilage is discussed.

Clinical manifestations and diagnostic approach to metastatic cancer of the mandible.

In a 12-month period, metastatic cancer was diagnosed in eight patients. Six of them presented with pain mimicking toothache, temporomandibular joint disorders or trigeminal neuralgia, while two showed osteopenic bone lesions in the panoramic radiography, and perimandibular swelling. Anesthesia of the lower lip was the only common clinical feature. In seven of the eight patients, a whole body bone scintigraphy and single photon emission computed tomography (SPECT) of the skull in combination with a whole body and SPECT anti-granulocyte (Tc-99m MAK 250/183) bone marrow scintigraphy was performed. One patient did not have combined scintigraphy performed secondary to severe systemic illness. In six of the seven, the results were conclusive for a metastatic bone lesion. Biopsies confirmed three patients to have a previously unrecognized primary cancer, one patient to have previously unrecognized recurrent cancer, and three patients to exhibit new metastatic spread of an already diagnosed cancer. Histology revealed breast, lung, renal cancer and a malignancy of inconclusive origin. In the remaining patient, combined scintigraphy suggested osteomyelitis, yet biopsy revealed a prostate cancer metastasis with acute inflammatory cell infiltration. Thus, the scintigraphy pattern of a hot spot in the bone scan and a cold lesion in the bone marrow scintigraphy is highly suggestive of a mandibular metastasis, if accompanied by anesthesia of the lower lip.

Bioincompatibility of dialyzer membranes may have a negative impact on outcome of acute renal failure, independent of the dose of dialysis delivered: a retrospective multicenter analysis.

The mortality rate of critically ill patients with acute renal failure (ARF) has remained high. The impact of vigorous intermittent hemodialysis (IHD) on the outcome of ARF has not been validated. In this retrospective multicenter analysis, 154 patients with ARF were treated daily (intensive) or on alternate days (conventional) using complement and cell activating cuprophane (bioincompatible) or high-flux polysulfone dialyzer membranes with insignificant effects on circulating complement or cells (biocompatible). At initiation of IHD, all four groups were similar in patient characteristics and ARF factors. The use of synthetic membranes resulted in a reduced mortality rate (18% vs 45%; p < 0.001) and shorter duration of ARF (8 vs 15 sessions; p < 0.001). Daily IHD with cellulose based membranes tended to increase mortality rates compared with conventional cuprophane dialysis (37% vs 53%). Intensive IHD with polysulfone membranes resulted in a further decrease in overall mortality rates (15% vs 22%). This retrospective analysis shows that bioincompatibility of dialyzer membranes may be more important for the outcome of patients with ARF than the dose of dialysis. Its impact on outcome occurs independently of the dose of dialysis delivered.

Bioincompatible membranes place patients with acute renal failure at increased risk of infection.

The mortality of critically ill patients with acute renal failure (ARF) requiring hemodialysis remains high (> 50%), even though major improvements in the management of this disorder have been made. Sepsis has been identified as a major cause of death in ARF. Experimental data have suggested that bioincompatible membranes aggravate uremia induced neutrophil dysfunction. In the following two combined prospective, randomized, clinical studies, the effects of the biocompatibility of dialysis membranes on the susceptibility to infection were compared in 72 surgical and medical patients with ARF. The group of patients treated with biocompatible polyacrylonitrile membranes had a significantly lower incidence of bacterial infections and a lower relative and absolute mortality rate due to sepsis, compared to patients treated with bioincompatible cuprophane membranes. These investigations identified bioincompatibility as a factor that adversely affects the prognosis of critically ill patients with ARF.

Prevention of infective endocarditis associated with dental treatment and other medical interventions. National Heart Foundation.

The prevention of infective endocarditis is extremely important for people with valvular heart disease and other high-risk cardiac conditions. The following is the National Heart Foundation's updated recommendations for the prophylaxis of infective endocarditis. The recommended antibiotic regimens have changed considerably from the previous guidelines. In response to these guidelines, Pharmac has instituted a number of changes to the Schedule to reduce the barriers to prescribing the recommended drugs for this indication. Pharmac expects that the last of these drugs to be listed on the Schedule (cefuroxime axetil) will be in place by 1 October 1999. Prescriptions will need to be endorsed "prophylaxis for endocarditis". Therefore, any prescriber (doctor or dentist) will be able to prescribe the recommended drugs on an endorsed prescription but, until 1 October 1999, some of the drugs may not be fully subsidised. Pharmac will be informing prescribers of the details of these changes in the near future. The Ministry of Health has recently alerted practitioners to the possible risk of heart valve damage following the long-term use of weight-loss drugs fenfluramine (Ponderax) and dexfenfluramine (Adifax). All patients who have taken these drugs for longer than 3 months should have a clinical check and, if any abnormality is detected, should be referred to a cardiologist. If mild or greater aortic or mitral regurgitation is present, antibiotic prophylaxis against endocarditis is recommended.--Boyd A Swinburn, Medical Director, National Heart Foundation.

TdTomato and EGFP identification in histological sections: insight and alternatives.

Tandem dimer Tomato (tdTomato) provides a useful alternative to enhanced green fluorescent protein (eGFP) for performing simultaneous detection of fluorescent protein in histological sections together with fluorescence immunohistochemistry (IHC). eGFP has many properties that make it useful for cell labeling; however, during simultaneous fluorescence IHC, the usefulness of eGFP may be limited. This limitation results from a fixation step required to identify eGFP in histological tissue sections that can mask antibody epitopes and adversely affect staining intensity. An alternative fluorescent protein, tdTomato, may assist concurrent detection of fluorescent protein within tissue sections and fluorescence IHC, because detection of tdTomato does not require tissue fixation. Tissue sections were obtained from various organs of mice ubiquitously expressing eGFP or tdTomato that were either unfixed or fixed with 4% paraformaldehyde. These tissues later were combined with fluorescence IHC. Both eGFP and tdTomato displayed robust signals in fixed frozen sections. Only tdTomato fluorescence, however, was detected in unfixed frozen sections. Simultaneous detection of fluorescence IHC and fluorescent protein in histological sections was observed only in unfixed frozen tdTomato tissue. For this reason, tdTomato is a useful substitute for eGFP for cell labeling when simultaneous fluorescence IHC is required.