Utility of scintigraphic methods in patients with fever of unknown origin

BACKGROUND: We assessed the utility of scintigraphy with indium 111-labeled polyclonal human IgG scintigraphy in patients with fever of unknown origin that fulfilled the criteria of temperature of 38.3 degrees C or more for at least 3 weeks and no diagnosis during 1 week of hospital admission. We compared the utility of this technique with results of scintigraphic techniques reported in the literature. METHODS: Data for all patients seen at our university hospital in whom 111In-IgG scanning was performed were analyzed and checked for the criteria for fever of unknown origin. The literature on the utility of scintigraphic techniques in patients with fever of unknown origin was reviewed. RESULTS: We studied 24 patients with fever of unknown origin. In 13 patients, focal 111In-IgG accumulation was observed. In nine (38%) of those, the positive 111In-IgG scintigram led to the final diagnosis; in the other four patients (17%), the scintigraphic findings were not helpful. In the 11 patients with negative 111In-IgG scans, extensive diagnostic workup produced no infection as the final diagnosis in nine patients (38%), one had an abscess in a renal cyst that was detected several months later, and in the other the cause of fever was an infected intravenous line. The overall sensitivity and specificity of 111In-IgG scintigraphy were 81% and 69%, respectively. The positive predictive value was 69% and the negative predictive value was 82%. CONCLUSIONS: Our results show that 111In-IgG scintigraphy significantly contributed to the diagnostic process in patients with fever of unknown origin. A positive scan increased the likelihood of finding the cause of the fever, and a negative scan ruled out an inflammatory component with a high degree of certainty. These data compare favorably with data in the literature concerning other radiopharmaceuticals; a larger prospective evaluation of this technique is indicated.     

High blood pressure. A side effect of drugs, poisons, and food

A variety of therapeutic agents or chemical substances can induce either a transient or a sustained increase in blood pressure. These agents increase arterial pressure by either causing sodium retention and extracellular volume expansion or directly or indirectly activating the sympathetic nervous system. Some agents act directly on arteriolar smooth muscle. For certain agents, the mechanism of pressure elevation is mixed or unknown. Paradoxically, some agents that are used to lower arterial pressure may acutely increase arterial pressure. Also, a rebound increase in pressure may be encountered after discontinuation of certain antihypertensive agents. In general, these chemically induced increases in arterial pressure are small and transient; however, severe hypertension involving encephalopathy, stroke, and irreversible renal failure has been reported. Careful evaluation of a patient's drug regimen may identify chemically induced hypertension and prevent the need for evaluation and therapy. This study reviews the therapeutic agents or chemical substances that elevate blood pressure and their mechanisms of action.     

Intermodality, retrospective image registration in the thorax

The purpose of this study was to develop an accurate, retrospectively applicable procedure for registering thoracic studies from different modalities in a short amount of time and with minimal operator intervention. METHODS: CT and PET studies were acquired from six patients. The pleural surfaces in both image sets were determined by segmenting based on 50% of the maximum soft-tissue value in the study. These surfaces were converted into three-dimensional volumes and used to register the CT and PET studies in three dimensions using a sum of least squares fitting approach. The registered PET study was then displayed in a hot metal scale overlayed on top of the gray scale CT study. The accuracy of the fit was evaluated through a phantom study and preliminary clinical evaluation. RESULTS: A phantom study was performed to determine the limits of this technique. The accuracy was determined to be less than 2.3 mm in the x and y direction and 3 mm in the z direction. Preliminary clinical evaluation was also performed with encouraging results. CONCLUSION: This technique accurately registers PET and CT images of the thorax, retrospectively, without the need for external fiducial markers or other a priori action.     

UVB-induced suppression of the mixed epidermal cell lymphocyte reaction is critically dependent on irradiance

The mixed epidermal cell lymphocyte reaction (MECLR) is a commonly used method to study the effects of ultraviolet B (UVB) radiation on the skin immune system. In UVB experiments dosimetry is very important. The influence of irradiance on the MECLR was studied in vitro using Philips FS40 lamps with variable UV intensities. Irradiation of isolated epidermal cells with high irradiance impaired the alloactivating capacity more than irradiation with low irradiance. In vivo, the influence of long-term UVB exposure on the MECLR was studied by treating normal healthy volunteers with suberythemagenic doses of UVB thrice weekly during 4 weeks. The first set of experiments, using low irradiance Sylvania UV-21 F75/85 W lamps, resulted in a decrease of MECLR responses of 83.1%. In the second set of experiments performed a year later, employing an identical protocol except for the use of high irradiance Waldmann UV-21 F85/100 W lamps, an increase of MECLR responses of 99.7% was observed. Volunteers of both sets of experiments received equal doses of UVB. In conclusion, this study shows that in vitro UVB-induced suppression of the MECLR is critically dependent on irradiance and therefore might explain contradictory results described in the literature. The in vivo data suggest that, comparable to the in vitro experiments, irradiance may influence the effects of UVB irradiation in vivo. Further experiments should prove whether this is indeed the case.     

A long-term follow-up study of patients with ischaemic heart disease versus patients with nonspecific chest pain

Ninety consecutive patients who were admitted to hospital with acute chest pain were followed-up five years later. At the time of the original admission, all of the patients received a detailed physical and psychiatric evaluation. Seventy-one patients were diagnosed as having ischaemic heart disease, and 19 were diagnosed as having nonspecific chest pain. Patients with nonspecific pain were younger, consumed greater amounts of alcohol, smoked more than their organic counterparts, and were more likely to suffer from psychiatric disorder. The five-year assessment was carried out using a self-report questionnaire. Of the original 71 patients with ischaemic heart disease, 14 had died; 43 questionnaires were returned, 80.2% of the original sample. Sixteen (84.9%) of the patients with nonspecific pain were followed up; none had died. Both groups were predominantly male. The patients with nonspecific pain still smoked more than the patients with ischaemic heart disease, and they had significantly more symptoms of anxiety. The overall prevalence of psychiatric morbidity remained high, however, in both groups. Patients who had psychiatric illness at the time of the original assessment were more anxious at follow-up and more likely to complain of chest pain than those who had been well. Patients with nonspecific chest pain continued to seek treatment on a regular basis from their general practitioners either for chest pain or for other symptoms, but few were in frequent contact with hospital services. The possible preventive effects of psychiatric intervention at an earlier stage in both groups of patients needs to be investigated.     

Arthroscopic Bankart repair with the Suretac device. Part I: Clinical observations

Although arthroscopic Bankart repair has become an accepted surgical stabilization technique for anterior shoulder instability, the failure rate remains unacceptably high. Little information is available concerning healing of the Bankart repair. The purpose of this article is to clarify this issue by analyzing a cohort of 15 patients who underwent a "second-look" arthroscopy to evaluate and treat pain or recurrent instability following arthroscopic Bankart repair with the Suretac device (Acufex Microsurgical, Mansfield, MA). "Second-look" arthroscopy was performed at an average of 9 months following the index surgical procedure. The reasons for this second surgery were recurrent instability in 7, pain in 6, and pain and stiffness in 2. In the 7 patients with recurrent instability, the Bankart repair was found to be completely healed in 3 (43%), partially healed in 1 (14%), and had recurred in 3 (43%); however, 6 of 7 were observed to have lax capsular tissue. In 4 of these cases, retrospective review of the index surgical procedure showed that a technical error had been made during the repair. Two cases had biopsy of the repair site on "second-look" at 6 to 8 months, and this showed residual polyglyconate polymer debris surrounded by a histiocytic infiltrate. In the remaining 8 cases with stable shoulders, the Bankart repair had completely healed in 5 cases (62.5%) and partially healed in 3 cases (37.5%). The higher failure rate with this approach compared with open approaches appears to result from improper patient selection and errors in surgical technique. There is some question concerning healing strength of the Bankart repair, although complete healing of the Bankart does not seem to be a prerequesite for shoulder stability. Success of the procedure might be expected to improve by selecting only patients with unidirectional, posttraumatic, anterior instability who are found to have a discrete Bankart lesion and well-developed ligamentous tissue.     

Large-scale screening for factor V Leiden mutation in a north-eastern German population

A 37-year-old man was referred with thoracic pain after a deceleration trauma. He also had a cerebral contusion and a wrist fracture. There were no sings of hypovolemic shock. Computerized tomography (CT) of the chest and transoesophageal echocardiography (TEE) demonstrated a type B aortic dissection originating just distal to the left subclavian artery. There was a patent false lumen without rupture or distal ischaemia. Conservative treatment was given. A paralytic ileus developed and abdominal complaints persisted for several months. Angiography showed normal patency of mesenteric vessels. On follow-up, 3 years after the accident a slight aortic dilation was found on CT thorax without development of a post-dissection aneurysm. Blunt thoracic injury to the aorta usually gives rise to aortic rupture in the region of the isthmus, which can be complete or partial. In the latter case a false aneurysm may develop. An intimal tear after blunt trauma leading to type B aortic dissection rarely occurs. General principles regarding treatment of type B dissection also apply to this particular condition.