The value of autopsy in preterm infants at a Swedish tertiary neonatal intensive care unit 2002-2018

Reliable data on causes of death (COD) in preterm infants are needed to assess perinatal care and current clinical guidelines. In this retrospective observational analysis of all deceased preterm infants born < 37 weeks’ gestational age (n = 278) at a Swedish tertiary neonatal intensive care unit, we compared preliminary COD from Medical Death Certificates with autopsy defined COD (2002–2018), and assessed changes in COD between two periods (period 1:2002–2009 vs. period 2:2011–2018; 2010 excluded due to centralized care and seasonal variation in COD). Autopsy was performed in 73% of all cases and was more than twice as high compared to national infant autopsy rates (33%). Autopsy revised or confirmed a suspected preliminary COD in 34.9% of the cases (23.6% and 11.3%, respectively). Necrotizing enterocolitis (NEC) as COD increased between Period 1 and 2 (5% vs. 26%). The autopsy rate did not change between the two study periods (75% vs. 71%). We conclude that autopsy determined the final COD in a third of cases, while the incidence of NEC as COD increased markedly during the study period. Since there is a high risk to determine COD incorrectly based on clinical findings in preterm infants, autopsy remains a valuable method to obtain reliable COD.

Postmortem magnetic resonance imaging vs autopsy of second trimester fetuses terminated due to anomalies

Introduction

Our aim was to investigate the accuracy of postmortem fetal magnetic resonance imaging (MRI) compared with fetal autopsy in second trimester pregnancies terminated due to fetal anomalies. A secondary aim was to compare the MRI evaluations of two senior radiologists.

Material and methods

This was a prospective study including 34 fetuses from pregnancies terminated in the second trimester due to fetal anomalies. All women accepted a postmortem MRI and an autopsy of the fetus. Two senior radiologists performed independent evaluations of the MRI images. A senior pathologist performed the fetal autopsies. The degree of concordance between the MRI evaluations and the autopsy reports was estimated as well as the consensus between the radiologists.

Results

Thirty‐four fetuses were evaluated. Sixteen cases were associated with the central nervous system (CNS), five were musculoskeletal, one cardiovascular, one was associated with the urinary tract, and 11 cases had miscellaneous anomalies such as chromosomal aberrations, infections and syndromes. In the 16 cases related to the CNS, both radiologists reported all or some, including the most clinically significant anomalies in 15 (94%; CI 70%‐100%) cases. In the 18 non‐CNS cases, both radiologists reported all or some, including the most clinically significant anomalies in six (33%; CI 5%‐85%) cases. In 21 cases (62%; CI 44%‐78%), both radiologists held opinions that were consistent with the autopsy reports. The degree of agreement between the radiologists was high, with a Cohen's Kappa of 0.87.

Conclusions

Postmortem fetal MRI can replace autopsy for second trimester fetuses with CNS anomalies. For non‐CNS anomalies, the concordance is lower but postmortem MRI can still be of value when autopsy is not an option.

Blood as Tracer for CSF Circulation after Subarachnoidal Hemorrhage

The amount and distribution of blood in the cerebrospinal fluid following subarachnoid hemorrhage can be monitored with CT. An investigation of 110 patients was performed retrospectively in 100 patients with a total of 132 CT examinations, and prospectively in 10 patients with 40 CT examinations. During the days following the hemorrhage, the blood was redistributed within the subarachnoid space and eventually reabsorbed. The blood in the basal cisterns was cleared first, whereas the amount of blood in the cortical sulci appeared to increase after a few days, later to be cleared. It is concluded that the redistribution of the blood reflects the circulation of the cerebrospinal fluid, and that the erythrocytes thus act as tracers of this circulation. The amount of blood within the ventricular system was correlated to the size of the ventricles; patients with large amounts of blood within the subarachnoid space had hydrocephalus more often than other patients.

Combined Embolization and Gamma Knife Radiosurgery for Cerebral Arteriovenous Malformations

In a study of 46 patients with cerebral arteriovenous malformations (AVMs) the value of combining embolization and gamma knife radiosurgery was assessed. In 35 patients with large grade III to V AVMs (Spetzler-Martin system) staged combined treatment was planned. In 11 patients, radiosurgery complemented embolization for a residual AVM. The number of embolization sessions ranged from 1 to 7 (median 2). Twenty-six patients needed multiple embolization sessions. In 28 patients the grade of AVMs decreased as a result of embolization. In 16 patients collateral feeding vessels developed after embolization which made delineation of the residual nidus difficult. The time lag between the last embolization and radiosurgery ranged from 1 to 24 months (median 4). Nineteen of 35 large grade III to V AVMs were possible to treat by radiosurgery following embolization. In the 46 patients complications occurred in 9 from embolization and in 2 from radiosurgery. Two patients had transient and 9 had permanent neurologic deficits. It is concluded that embolization facilitates radiosurgery for some large AVMs and therefore this combined treatment has a role in the management of AVMs.

Diffusion-weighted MR and apparent diffusion coefficient in the evaluation of severe brain injury

Purpose: To study apparent diffusion coefficient (ADC) maps in severely brain-injured patients.

Material and Methods: Four deeply comatose patients with severe brain injury were investigated with single-shot, diffusion-weighted, spin-echo echoplanar imaging. The tetrahedral diffusion gradient configuration and four iterations of a set of b-values (one time of 0 mm2/s, and four times of 1000 mm2/s) were used to create isotropic ADC maps with high signal-to-noise ratio. ADC values of gray and white matter were compared among patients and 4 reference subjects.

Results: One patient was diagnosed as clinically brain dead after the MR examination. The patient's ADC values of gray and white matter were significantly lower than those of 3 other brain-injured patients. In addition the ADC value of white matter was significantly lower than that of gray matter.

Conclusion: The patient with fatal outcome shortly after MR examination differed significantly from other patients with severe brain injury but non-fatal outcome, with regard to ADC values in gray and white matter. This might indicate a prognostic value of ADC maps in the evaluation of traumatic brain injury.

Orbital Phlebography for Differentiation between Multiple Sclerosis and Venous Vasculitis in Subacute Blindness

Thirteen consecutive patients with subacute unilateral loss of vision and periorbital pain but without pathology of the fundus or increased erythrocyte sedimentation rate, were investigated with visual evoked response, electrophoresis of serum and cerebrospinal fluid, and orbital phlebography. Seven of these patients were found to suffer from multiple sclerosis. The remaining 6 were considered to have venous vasculitis. There was a spontaneous recovery from visual impairment in all patients with multiple sclerosis, but not in patients with venous vasculitis. Of the latter patients, only two, who were treated with steroids within the first four days after onset of symptoms, regained vision. It appears that orbital phlebography is the diagnostic procedure of choice for proper management of patients with subacute loss of vision.

Computed Tomography of the Brain in Cases with Venous Vasculitis Compared with an Age-Matched Reference Group

Patients with a particular, steroid-sensitive headache and often characteristic pathology at orbital phlebography, have been suggested to suffer from venous vasculitis. Fifty such patients were examined with computed tomography (CT) of the brain. The findings were compared with those of an age-matched reference group selected at random to represent normal subjects. The CT examinations were analyzed with respect to size of lateral ventricles and signs of atrophy. In both groups, there was a significant increase of atrophy with age. There was also a significantly higher degree of atrophy in the patient group as compared with the reference group. The findings indicate that the supposedly underlying venous vasculitis is related to early aging and atrophy of the brain.

Comparison of the Accumulation Kinetics of L-(Methyl-11C)-Methionine and D-(Methyl-11C)-Methionine in Brain Tumors Studied with Positron Emission Tomography

Five patients with glioma were examined with positron emission tomography after the administration of 11C-L-methionine and at a following day with 11C-D-methionine. The rates of accumulation of the tracers were determined in the tumor and in the normal brain tissue according to a graphical technique of Patlak et coll. (24). The accumulation rates for L-methionine were on the average 2.4 times higher than those of D-methionine in the tumors. The corresponding ratio for normal brain tissue was 2.3. It is concluded that in this group of tumors without obvious blood-tumor-barrier breakdown, a stereospecific process with similar properties as in the normal brain tissue, is responsible for the accumulation of the labelled methionine.

Positron Emission Tomography Compared with Magnetic Resonance Imaging and Computed Tomography in Supratentorial Gliomas Using Multiple Stereotactic Biopsies as Reference

Ten patients with findings at computed tomography (CT) suggesting intracranial supratentorial glioma were investigated to compare the diagnostic efficacy of this technique with that of positron emission tomography (PET) using 11C-methionine and exminations with magnetic resonance (MR). The findings were related to histopathologic examination of serial stereotactic biopsies, which were guided by the appearance of the lesions on PET examination. To obtain corresponding slice orientation with the different examination techniques, an individually shaped helmet fixation was used. However, in 3 cases this fixation device could not be used for MR. Histopathologic diagnosis, obtained in all cases from multiple target stereotactic biopsies, included glioma in 9 patients and reactive gliosis in one case. A detailed comparison of the three imaging techniques and the findings at stereotactic biopsies was possible in 7 patients, while in 3 patients comparison with MR was less exact due to the patient's refusal to wear the helmet during this examination. MR was the most accurate method for outlining the total extent of a lesion, i.e. the tumor and the edema surrounding it. Four lesions had homogeneous signal characteristics and in 6 lesions two (or more) compartments could be distinguished with MR. In 5 cases the MR findings were in complete agreement with the histopathologic findings. However, a thorough correlation between signal characteristics and histology was not possible. Using PET the occurrence and the extent of tumor tissue was correctly predicted in 7 patients. The PET was normal in one case. Findings at CT were in agreement with the histopathologic diagnosis in 5 patients. MR was the most sensitive method for the detection of lesions. PET using methionine appeared to have a somewhat higher capacity to outline correctly the true extent of a tumor. The combination of CT and PET was superior to MR for determining the type and grade of the tumors.

Target Delineation in Radiosurgery for Cerebral Arteriovenous Malformations

A study of 6 selected arteriovenous malformation (AVM) patients was performed to investigate the feasibility of delineating an AVM on MR images and to compare the AVM volume outlined on different images. Conventional stereotaxic angiograms, stereotaxic MR images and MR angiograms using several different pulse sequences were obtained prior to radiosurgery. Treatment plans were made from the conventional stereotaxic angiograms. These plans were then transferred to a separate dose planning computer which displayed the MR images with the superimposed isodose lines. The radiated volumes of AVM and brain tissue were measured from these MR images. Last, an assessment was made of the radiation volume needed for an appropriate treatment of the AVM if the treatment plan was made from the MR images rather than from the conventional stereotaxic angiogram. It was possible to delineate medium and large size AVM nidi on stereotaxic MR images based on an integration of information obtained from various pulse sequences. The estimated volumes of the AVM nidi were found to be larger on the conventional stereotaxic angiograms than on the stereotaxic MR images. Consequently, a dose plan based on a conventional stereotaxic angiogram would result in a higher integral dose to the brain with the same target dose. By using reliable MR information it is expected that the volume of brain exposed to radiation could be decreased and the adverse effects of stereotactic radiosurgery for AVM thereby minimized.

Application of a Kinetic Model on the Methionine Accumulation in Intracranial Tumours Studied with Positron Emission Tomography

Eleven patients were studied with positron emission tomography (PET) using 11C-methionine. They all had low-grade astrocytomas (Kernohan grade II). The PET studies were analyzed with a metabolic model to obtain values for the influx, the accumulation rate and the partition coefficient of methionine in normal and tumourous tissue. Seven of the tumours showed an increased accumulation of methionine as compared with normal tissue on the static PET scans and also had higher values as to the kinetic parameters. Four tumours had a methionine accumulation equal to or lower than that of normal tissue and the kinetic parameters were also lower. Application of the kinetic model did not aid significantly in the delineation of the tumours. There was a correlation between the three parameters indicating an adaption of the transport of methionine to the regional metabolic demand. The accumulation rate for normal cortical tissue was 0.49 nmol/g/min, the influx 0.97 nmol/ml and the partition coefficient 0.45 ml/g. These values are considerably higher than those previously reported. The differences might be attributed to differences in the corrections introduced for i.a. the occurrence of labelled metabolites in serum. With the use of a kinetic model, more information about the tracer is utilized and gained compared with the previously used graphic approach.

Acute-Sinus Thrombosis in a Child with Antibodies against Cardiolipins

A case of thrombosis of the straight sinus and the left transverse sinus in an 11 year old boy is described. The patient had a history of slight trauma followed by infection of the upper airways and presented with severe impressive and expressive dysphasia and stupor.

He was treated with in situ fibrinolysis. Despite successful local fibrinolysis and thrombectomy with a balloon catheter the patient rethrombosed his left transverse sinus several times and had a late thrombosis of his jugular vein.

Nevertheless, flow in the left sigmoid sinus was facilitated and focal brain oedema was significantly reduced.

Serum levels of antibodies against cardiolipins, associated with venous thrombosis, were elevated and interfered with reagents used for measuring the activated partial tromboplastin time, causing it to be falsely prolonged with subsequent underdosage of heparin. He was treated with oral anticoagulants for one year after the episode and recovered completely.

MuSK: a new target for lethal fetal akinesia deformation sequence (FADS)

BACKGROUND

Fetal akinesia deformation sequence syndrome (FADS, OMIM 208150) is characterised by decreased fetal movement (fetal akinesia) as well as intrauterine growth restriction, arthrogryposis, and developmental anomalies (eg, cystic hygroma, pulmonary hypoplasia, cleft palate, and cryptorchidism). Mutations in components of the acetylcholine receptor (AChR) pathway have previously been associated with FADS.

METHODS AND RESULTS

We report on a family with recurrent fetal loss, where the parents had five affected fetuses/children with FADS and one healthy child. The fetuses displayed no fetal movements from the gestational age of 17 weeks, extended knee joints, flexed hips and elbows, and clenched hands. Whole exome sequencing of one affected fetus and the parents was performed. A novel homozygous frameshift mutation was identified in muscle, skeletal receptor tyrosine kinase (MuSK), c.40dupA, which segregated with FADS in the family. Haplotype analysis revealed a conserved haplotype block suggesting a founder mutation. MuSK (muscle-specific tyrosine kinase receptor), a component of the AChR pathway, is a main regulator of neuromuscular junction formation and maintenance. Missense mutations in MuSK have previously been reported to cause congenital myasthenic syndrome (CMS) associated with AChR deficiency.

CONCLUSIONS

To our knowledge, this is the first report showing that a mutation in MuSK is associated with FADS. The results support previous findings that CMS and/or FADS are caused by complete or severe functional disruption of components located in the AChR pathway. We propose that whereas milder mutations of MuSK will cause a CMS phenotype, a complete loss is lethal and will cause FADS.

Streptokinase treatment of deep venous thrombosis of the lower extremity. Clinical, phlebographic and plethysmographic evaluation of early and late results

The investigation comprises 19 patients with acute deep vein thrombosis of the leg treated with streptokinase. The acute clinical symptoms rapidly subsided in 15 patients. Phlebography, performed immediately after treatment, revealed complete thrombus regression in 7 cases, restoration of venous flow but remnants of thrombi in 4 and no effect in 7. One woman was not evaluated radiologically due to pregnancy. The phlebographic restoration seemed to be correlated to the duration of the thrombotic symptoms. Follow-up examinations 6-50 months after the thrombotic incident demonstrated normal phlebograms in 8 patients, all of whom were also free from post-thrombotic symptoms. Venous occlusion plethysmography confirmed that these patients had a normal venous outflow capacity and valvular function in the relevant limbs. By contrast, the remaining 11 patients, with more or less extensive remnants of thrombi at the follow-up phlebography, were found to have plethysmographic signs of venous obstruction and sometimes also valvular insufficiency. The results indicate that thrombolytic treatment is able to give a complete and lasting anatomical and functional restitution of the deep veins after an acute thrombosis in the leg, provided that treatment is induced early enough.

Effects of 21 days of bed rest, with or without artificial gravity, on nutritional status of humans

Spaceflight and bed rest models of microgravity have profound effects on physiological systems, including the cardiovascular, musculoskeletal, and immune systems. These effects can be exacerbated by suboptimal nutrient status, and therefore it is critical to monitor nutritional status when evaluating countermeasures to mitigate negative effects of spaceflight. As part of a larger study to investigate the usefulness of artificial gravity as a countermeasure for musculoskeletal and cardiovascular deficits during bed rest, we tested the hypothesis that artificial gravity would have an effect on some aspects of nutritional status. Dietary intake was recorded daily before, during, and after 21 days of bed rest with artificial gravity (n = 8) or bed rest alone (n = 7). We examined body composition, hematology, general blood chemistry, markers of oxidative damage, and blood levels of selected vitamins and minerals before, during, and after the bed rest period. Several indicators of vitamin status changed in response to diet changes: serum alpha- and gamma-tocopherol and urinary 4-pyridoxic acid decreased (P < 0.001) and plasma beta-carotene increased (P < 0.001) in both groups during bed rest compared with before bed rest. A decrease in hematocrit (P < 0.001) after bed rest was accompanied by a decrease in transferrin (P < 0.001), but transferrin receptors were not changed. These data provide evidence that artificial gravity itself does not negatively affect nutritional status during bed rest. Likewise, artificial gravity has no protective effect on nutritional status during bed rest.

Transposon-based interferon gamma gene transfer overcomes limitations of episomal plasmid for immunogene therapy of glioblastoma

Despite improvements in gene delivery technology, transient expression of plasmid DNA has limited the efficacy of nonviral vectors applied to cancer gene therapy. We previously developed plasmid DNA vectors capable of transgene integration and long-term expression in human glioblastoma cells by utilizing the Sleeping Beauty (SB) transposable element. In this study, we compared the efficacy of interferon gamma (IFN-gamma) immunogene therapy using episomal or SB vectors in a syngeneic GL261 glioma model. Gene delivery was achieved by intratumoral convection-enhanced delivery of DNA/polyethylenimine complexes. Only mice treated with SB transposase-encoding DNA to facilitate chromosomal integration exhibited a significant increase in survival (P<0.05). SB-mediated intratumoral gene transfer caused sustained IFN-gamma expression assessed by reverse transcription-polymerase chain reaction, of both vector-derived and endogenous IFN-gamma, whereas expression following episomal plasmid gene transfer was undetectable within 2 weeks. Median survival was enhanced further when SB-mediated IFN-gamma gene transfer was combined with CpG oligodeoxynucleotides as adjuvant therapy. Prolonged survival positively correlated with tumor regression measured by in vivo bioluminescent imaging, and enhanced T-cell activation revealed by the ELISPOT assay. SB appears to improve the efficacy of cytokine gene therapy using nonviral vectors by enhancing the duration of transgene expression.

Lymphocytic hypophysitis: report of two biopsy-proven cases and one suspected case with pituitary autoantibodies

Lymphocytic hypophysitis (LyH) is a rare inflammatory disease, considered to be autoimmune. LyH has mainly been reported in females and in relation to pregnancy or the post-partum period. We describe a 73-yr-old woman and a 63-yr-old male who were evaluated at our clinic because of pituitary hormone deficits. Both patients had pituitary masses suggestive of a pituitary adenoma on magnetic resonance imaging (MRI). Transsphenoidal pituitary surgery was performed and histopathological examinations revealed LyH in both cases. Clinical, laboratory, radiological and the histopathological findings in these two patients are discussed in detail. In addition, we report on a 79-yr-old man with partial hypopituitarism and empty sella. Screening of a human pituitary cDNA library with his serum revealed autoantibodies against secretogranin II. This is a protein commonly present in human gonadotrophs, thyreotrophs and corticotrophs. Since the patient selectively showed the corresponding pituitary insufficiencies, we speculate on an autoimmune background. Further studies may ascertain the importance of secretogranin II autoantibodies as markers for LyH.

FDG-PET on irradiated brain tumor: ten years' summary

PURPOSE

To evaluate FDG-PET in post-radiotherapy differentiation of tumor recurrence/malignant degeneration and radiation reaction, and to assess the role of PET in terms of survival.

MATERIAL AND METHODS

117 consecutive patients with a total of 156 FDG-PET examinations with positive but non-diagnostic MRI and/or CT were included. Final diagnosis was based on histopathology or correlated with radiologic and clinical follow-up. Brain metastases from lung carcinomas were further studied separately. Survival time was analysed using the Kaplan-Meier method.

RESULTS

There were 61 true-positive, 2 false-positive, 15 false-negative, and 51 true-negative PET examinations; 5 positive and 22 negative PET examinations were indeterminate. The positive predictive value of a PET examination was 96% in all and 100% in brain metastases from lung carcinoma. The negative predictive value based on the histopathologic results was 55.6%. Survival time was significantly longer in patients with negative PET.

CONCLUSION

FDG-PET is a valuable tool in the detection of tumor recurrence, especially lung carcinoma metastasis. FDG uptake is a prognostic marker.

Comparison of ultrasound and autopsy findings in pregnancies terminated due to fetal anomalies

OBJECTIVE

To compare antenatal diagnoses with autopsy findings in pregnancies terminated after ultrasound detection of fetal anomalies. A second aim was to study the quality of antenatal fetal diagnosis over time.

DESIGN

Retrospective, multicenter study over two consecutive six-year periods in Uppsala and Stockholm.

SETTING

Cases were identified through fetal autopsy reports.

SUBJECTS

Three hundred and twenty-eight fetuses from pregnancies terminated between 1992 and 2003 because of ultrasonographically diagnosed anomalies.

MAIN OUTCOME MEASURES

The findings at the last ultrasound examination were compared with the autopsy reports.

RESULTS

In 299 cases (91.2%) ultrasound findings either exactly matched or were essentially similar to the autopsy findings. In 23 cases (7%) ultrasound findings were not confirmed at autopsy, but the postnatal findings were at least as severe as the antenatal ones. In six cases (1.8%) termination was performed for an anomaly which proved to be less severe than was predicted by ultrasound. The number of such cases was the same in both six-year periods, while the total number of cases increased from 113 in the first to 215 in the second period. Fetal examination provided further diagnostic information in 47% of the cases. In 10% a syndrome was disclosed.

CONCLUSION

Termination of pregnancy was not always based on a correct antenatal diagnosis. All fetuses but one from terminated pregnancies had evident anomalies. In six cases (1.8%) the decision to terminate was based on suboptimal prognostic and diagnostic information. Fetal autopsy by an experienced perinatal pathologist is essential to provide a definitive diagnosis.

No evidence for autoimmunity as a major cause of the empty sella syndrome

OBJECTIVE

The cause of empty sella syndrome (ESS) remains largely unknown. We measured eleven organ-specific autoantibodies in serum in order to evaluate possible autoimmune components in ESS.

PATIENTS

Thirty patients with ESS and 50 healthy blood donors participated in the study.

MEASUREMENTS

Detection of pituitary autoantibodies was performed by immunoblotting with human pituitary cytosol as antigen. Thyroid peroxidase (TPO) and TSH receptor (TRAK) autoantibodies were analysed by radioimmunoassay. The remaining eight autoantibodies were detected by in vitro transcription and translation of the autoantigens and immunoprecipitation.

RESULTS

The majority of the ESS patients (18/30) exhibited no immunoreactivity at all. None of the remaining 12 ESS patients reacted against more than one autoantigen. No immunoreactivity was found more frequently among ESS patients than healthy blood donors. Pituitary autoantibodies were not correlated to the ESS patients' pituitary function or sellar size, although the results indicated a tendency of increased autoimmunity in patients with hypopituitarism and normal sella size respectively.

CONCLUSION

Detection of autoantibodies is a valuable tool in the diagnostic work-up of autoimmune diseases. By analysing a large number of organ-specific autoantibodies we found no evidence of ESS being associated with any specific autoimmune disease. The pathogenesis of ESS is believed to be heterogeneous and our findings suggest autoimmune components to be of minor importance. In some selective cases, ESS in combination with hypopituitarism may be the result of an autoimmune disease in the pituitary gland but this needs further investigation.

Familial risk of tumors associated with hereditary non-polyposis colorectal cancer: a Swedish population-based study

BACKGROUND

Familial clustering, which may be due to inherited predisposition, is seen in several common cancer types. The aim of this study was to assess the familial risk of tumors that are associated with hereditary non-polyposis colorectal cancer (HNPCC), a familial cancer syndrome that confers an increased risk of several cancer types, and is associated with a low age at onset.

METHODS

The National Swedish Cancer Registry and population registers were utilized to identify all tumors among the offspring of individuals who had developed any of the diagnoses included in the Amsterdam II criteria for HNPCC. In all, 204,358 offspring of 102,814 individuals with cancer of the colorectum, endometrium, upper urinary tract or small intestine were identified.

RESULTS

Significantly increased risks for several tumor types were demonstrated. If the parent was below age 50 at diagnosis, the offspring Standard Incidence Ratios (SIRs) were 3.6 for colon cancer, 3.8 for rectal cancer, 2.8 for gastric cancer, and 2.3 for ovarian cancer. Offspring who had both a parent and a sibling with HNPCC-associated cancer showed even higher SIRs for cancer of the colorectum, endometrium, ovary, and urinary tract. The highest values were observed in the subgroup whose parent had developed multiple primary tumors; SIR 34.0 for colon cancer, 17.9 for rectal cancer, 21.8 for endometrial cancer, and 5.8 for ovarian cancer.

CONCLUSIONS

The study demonstrates that there is an increased risk for several tumor types among individuals whose parents developed HNPCC-associated tumors, where a young age at diagnosis and development of multiple tumors in the parents lead to the highest SIRs.

Defective mismatch-repair in patients with multiple primary tumours including colorectal cancer

Individuals with an inherited predisposition to cancer development are at an increased risk of developing multiple tumours. Hereditary non-polyposis colorectal cancer (HNPCC) is one of the most common hereditary cancer syndromes and is estimated to account for approximately 2% of colorectal cancers. However, HNPCC individuals are at an increased risk of developing other tumour types such as cancers of the endometrium, urothelium and small intestine. We have utilised a population-based regional cancer registry to identify all patients with double primary colorectal cancers and at least one additional malignancy and characterised the tumour spectrum in this patient group. We subsequently selected those 47 individuals who had developed at least four malignancies, including two colorectal cancers, for studies of the tumour characteristics associated with HNPCC. In total, these individuals developed 209 tumours, 156 of which were successfully retrieved. Microsatellite instability (MSI), a phenomenon caused by defective mismatch-repair (MMR), was identified in 63/154 (41%) evaluable tumours with a MSI-high pattern in 59 and a MSI-low pattern in four tumours. All tumours were immunohistochemically stained for the MMR proteins MLH1 and MSH2, with loss of expression in 55/63 (87%) MSI tumours and in 2/89 (2%) microsatellite stable (MSS) tumours. This loss affected MLH1 in 24 tumours and MSH2 in 33 tumours. A concordant loss of expression for the same MMR protein in several tumours from the same individual, a pattern that strongly suggests an underlying germline MMR gene mutation, was found in 17/45 (38%) patients and affected MLH1 in 8 patients and MSH2 in 9 patients. We conclude that the development of multiple primary tumours, including synchronous or metachronous colorectal cancers, is associated with an increased frequency of MSI and loss of immunohistochemical expression of MLH1 and MSH2.

Patients with Primary brain tumours have elevated serum titres of antibodies to the myelin glycolipid sulphatide

Primary and metastatic brain tumours may result in an altered exposure of normal cellular components to the immune system inducing an immune response measurable in autoantibodies. One potential immunogenic molecule is sulphatide, the major acidic glycolipid in myelin. Thirty-eight sera from 31 patients with primary and metastatic brain tumours have, therefore, been analyzed for the presence of antisulphatide antibodies by an ELISA performed on thin layer chromatography plates. Twenty-eight of the thirty-eight sera (74%) showed a positive antibody titre to sulphatide. The antibody titres were significantly higher (p < 0.01) in sera from patients with primary brain tumours than in sera from those with metastases. The study lends support to the possibility that antisulphatide antibodies could contribute to tissue damage and this might facilitate the invasive growth in primary brain tumours by demyelination. However, the pathogenic significance of these autoantibodies remains to be further elucidated.

Volume measurement of cerebral arteriovenous malformations from angiography

We designed software for measuring the volume of cerebral arteriovenous malformations from angiography and validated it against prescription volumes in radiosurgery. We aimed to create a model for the risk for complications as a function of volume, based on established outcome prediction models for Gamma Knife radiosurgery, but without the need for dose planning. We created an application for computing the volume of cerebral arteriovenous malformations from the intersection of two X-ray cones in stereotactic space. Volume measurements were compared with prescription volumes from dose planning, in phantoms and in patients treated with Gamma Knife radiosurgery for cerebral arteriovenous malformations. Previous studies of 1128 treated patients were used to calculate the risk for complication as a function of the nidus volume. In 63 patients volumes measured with either method correlated, R2 = 0.85. Volume as measured with the intersecting cone model (ICM) correlated with predicted Gamma Knife radiosurgery complication rate, R2 = 0.84. The ICM can thus be used for measurement of AVM volumes less than 10 cm3 from angiography. Outcome models from Gamma Knife radiosurgery may be applied, but with reduced exactness. Standardised AVM volume measurement is valuable for comparing outcome and for quantification of volume reduction after therapy, notably embolisation. Thus the optimal management plan may be selected in conjunction with diagnostic or therapeutic angiography.

Relationship of Chlamydia pneumoniae infection to severity of human coronary atherosclerosis

BACKGROUND

Infection with Chlamydia pneumoniae has been postulated to play a pathogenic role in atherosclerosis. We examined the role of infection with C pneumoniae in relation to the extent of coronary atherosclerosis.

METHODS AND RESULTS

Coronary atherosclerosis was graded microscopically on a postmortem basis in a blinded fashion in 60 subjects as mild (n=18) or severe (n=42) atherosclerosis. Serum antibodies to C pneumoniae were measured by microimmunofluorescence test. Paraffin-embedded coronary artery specimens were examined for the presence of chlamydia by use of a genus-specific direct immunofluorescence monoclonal antibody. Frozen coronary artery specimens were examined by immunoperoxidase for the presence of C pneumoniae by use of a specific monoclonal antibody RR-402. Direct immunofluorescence was reactive in 86% of cases with severe atherosclerosis but in only 6% of cases with mild atherosclerosis (P<0.01), whereas immunoperoxidase staining was reactive in 80% and 38% of cases with severe and mild atherosclerosis, respectively (P<0. 01). Elevated IgG and IgA levels against C pneumoniae were not different in cases with severe and mild atherosclerosis (61% and 30% for severe atherosclerosis and 67% and 42% for mild atherosclerosis, respectively).

CONCLUSIONS

This study supports the hypothesis that intracellular infection with C pneumoniae may relate to the severity of atherosclerosis in some subjects. Serum antibody titers against C pneumoniae do not differentiate between severe and mild atherosclerosis.

Seropositivity against Chlamydia pneumoniae in patients with coronary atherosclerosis

BACKGROUND

Results of therapy in patients with unstable coronary syndromes with antibiotics directed against Chlamydia pneumoniae have been variable, perhaps due to the heterogeneity of patients in these trials.

HYPOTHESIS

The aim of the present study was to correlate the severity of coronary artery disease (CAD) with seropositivity against C. pneumoniae prospectively.

METHODS

We measured the frequency of seropositivity (IgG levels > or = 1/64 and IgA levels > or = 1/16 against Chlamydia pneumoniae) in 110 patients with CAD and in 49 controls.

RESULTS

As expected, traditional CAD risk factors were seen more often in patients with CAD than in controls. Mean values of total cholesterol (184 +/- 52 and 166 +/- 44 mg/dl, respectively) and triglyceride (143 +/- 60 and 112 +/- 63 mg/dl, respectively) in serum were significantly higher in patients with CAD than in controls (both p < 0.04). There were no significant differences between the two groups in serum high-density lipoprotein cholesterol (34 +/- 13 and 32 +/- 14 mg/dl, respectively) and lipoprotein (a) (Lp(a):241 +/- 247 and 223 +/- 263 mg/l, respectively) levels. The rate of IgG seropositivity was 52% (28/54) in patients with stable CAD, 41% (23/56) in patients with unstable CAD, and 35% in controls (p = NS). The rate of IgA seropositivity was 25% (14/54) in patients with stable CAD, 12% (6/49) in patients with unstable angina, and 12% (6/49) in controls (all p = NS).

CONCLUSIONS

Only a small percentage of patients with CAD demonstrate seropositivity against Chlamydia pneumoniae. Antibiotic therapy in these selected patients, but not in the remaining patients, may be considered rational. These considerations may underlie the failure to see consistent benefits of antibiotic therapy in patients with CAD.

[Familial hemophagocytic lymphohistiocytosis: diagnosis, treatment and pathophysiological mechanisms]

Familial hemophagocytic lymphohistiocytosis (FHL) is an invariably fatal disease typically seen in infancy and early childhood, with a median survival without therapy of two months. It is characterized by prolonged fever, hepatosplenomegaly, cytopenia, and deficient NK-cell activity and T-cell cytotoxic capacity. Severe neurological symptoms as well as coagulation disorders and abnormalities in liver function and lipid status may also develop. Since the mid 1980's there has been a remarkable increase in our understanding of this disease. In a large-scale international collaborative effort mediated through the Histiocyte Society, diagnostic criteria and an international treatment protocol (HLH-94) based on immunochemotherapy and BMT have been developed. A large proportion of affected children can now be cured and, moreover, successful chemotherapy in utero of FHL has been achieved. It has been shown that the symptoms and signs are mediated through a pronounced hypercytokinemia. Previous suggestions that FHL may be caused by a deficiency in apoptosis were recently confirmed when perforin gene defects were described, which may well explain the disastrous lymphohistiocytic accumulation and subsequent T-cell activation.

Tumor suppressor INK4: determination of the solution structure of p18INK4C and demonstration of the functional significance of loops in p18INK4C and p16INK4A

Since the structures of several ankyrin-repeat proteins including the INK4 (inhibitor of cyclin-dependent kinase 4) family have been reported recently, the detailed structures and the functional roles of the loops have drawn considerable interest. This paper addresses the potential importance of the loops of ankyrin-repeat proteins in three aspects. First, the solution structure of p18INK4C was determined by NMR, and the loop structures were analyzed in detail. The loops adapt nascent antiparallel beta-sheet structures, but the positions are slightly different from those in the crystal structure. A detailed comparison between the solution structures of p16 and p18 has also been presented. The determination of the p18 solution structure made such detailed comparisons possible for the first time. Second, the [1H,15N]HSQC NMR experiment was used to probe the interactions between p18INK4C and other proteins. The results suggest that p18INK4C interacts very weakly with dna K and glutathione S-transferase via the loops. The third aspect employed site-specific mutagenesis and functional assays. Three mutants of p18 and 11 mutants of p16 were constructed to test functional importance of loops and helices. The results suggest that loop 2 is likely to be part of the recognition surface of p18INK4C or p16INK4A for CDK4, and they provide quantitative functional contributions of specific residues. Overall, our results enhance understanding of the structural and functional roles of the loops in INK4 tumor suppressors in particular and in ankyrin-repeat proteins in general.

MR imaging with gadolinium in patients with and without post-lumbar puncture headache

PURPOSE

To study frequency and extent of meningeal enhancement in patients with and without post-lumbar puncture headache (PLPH) with cerebral MR with Gd-DTPA.

MATERIAL AND METHODS

Ten consecutive patients with PLPH and 9 consecutive patients without PLPH were included in the study. Nine of the PLPH patients were reinvestigated when the PLPH was over and all non-PLPH patients during the week after the lumbar puncture.

RESULTS

Eight of the 9 patients with PLPH showed more enhancement of meningeal structures during PLPH than when PLPH had disappeared. The differences were slight in 5, more marked in 2, and pronounced in 1 patient. The 9th patient showed no change at all. In the 9 patients without PLPH, there was mainly slight enhancement before lumbar puncture and no change in enhancement after lumbar puncture as compared with before.

CONCLUSION

PLPH is related to increased Gd-DTPA enhancement of the meninges, although the increase in enhancement during PLPH is minor in most cases. Pronounced enhancement of the meninges after lumbar puncture may predict long duration of the PLPH.

Optimising contrast-enhanced cranial CT for detection of brain metastases

PURPOSE

In order to optimise contrast-enhanced CT in the detection of brain metastases, we investigated how sensitivity was affected by an increase in contrast medium dose and a reduction in slice thickness.

MATERIAL AND METHODS

A total of 198 cases of known primary malignancy with suspected brain metastases were investigated in three consecutive contrast-enhanced CT examinations. The first was a standard CT examination with an injection of 100 ml contrast medium (300 mg I/ml) and a slice thickness of 10 mm. A further 100 ml contrast medium was given and the second examination was performed immediately afterwards with the same slice thickness as the first. This was followed by the third examination, which used a slice thickness of 5 mm. The standard contrast-enhanced CT images were compared with the double-dose images and with the images of reduced slice thickness (5 mm instead of 10 mm).

RESULTS

The double-dose images demonstrated an 8-18% increase in the number of brain metastases detected compared to the standard contrast-enhanced CT; the images of the 5-mm-thick slices showed a further 22-33% increase. The comparison between the standard contrast-enhanced CT images and the images with both thinner slices and the double dose of contrast medium demonstrated a 32-55% increase in the number of metastases detected.

CONCLUSION

A considerable increase in sensitivity (32-55%) in contrast-enhanced CT can be obtained by reducing the slice thickness and increasing the contrast medium dose. This optimised technique should be the method of choice in patients with known primary malignancy and suspected brain metastases.

X-ray angiography in stereotactic conditions: techniques and interest for interventional neuroradiology

This paper reports work in progress on X-ray angiography acquired under stereotactic conditions. The objective is to be able to match multimodality images (typically MRI and X-ray) without a stereotactic frame but with stereotactic precision. We have identified potential problems and have studied them in detail. We conclude that, although the overall application is feasible, much work remains to be done on the estimation of the X-ray system conic projection and on automatic matching based on vascular structures.

An algorithm for correction of distortion in stereotaxic digital subtraction angiography

An algorithm for correction of the geometrical distortion in digital subtraction angiography (DSA) images was developed. Originally invented for 3D X-ray angiography, the algorithm was implemented in a computer program designed to fulfil the specific needs of stereotaxic DSA. The algorithm is based on transformation of an image of a grid from a distorted image back into its original pattern. The same transformation is then applied pixel-by-pixel to the angiographic images, which are acquired in direct conjunction with the grid image, without moving the gantry. The algorithm was tested in phantom studies and in the clinical situation with seven patients in ten examinations. Comparisons were made between co-ordinate determinations made on conventional full-size cut film and those performed on uncorrected and corrected DSA images, using 30- and 23-cm fields of view. With our method of measurement we could not shown any remaining geometric distortion in the corrected DSA images. This distortion correction can, if properly applied, be used for high-precision stereotaxic DSA.

Radiosurgery for cavernous malformations

OBJECT

The authors examined 22 patients with cavernous malformations (CMs) who had undergone gamma knife radiosurgery (GKRS) to assess the value of this procedure in treating these lesions.

METHODS

At the Karolinska Hospital, GKRS was used to treat 23 patients with CMs during the period of 1985 through 1996. One of the patients was lost to follow up and the treatment results of the 22 remaining patients were analyzed. In the first half of the series, the CMs were treated with high doses of radiation (> 15-Gy dose to the periphery); in the second half of the series, lower doses were used. Nine of the 22 patients suffered a post-GKRS hemorrhage and six developed a radiation-induced complication (two of these patients experienced both). Some time after GKRS was performed, surgical removal of the CM had to be undertaken in four patients because of hemorrhage and in two patients because of radiation-induced complications. Four of the nine patients who experienced no post-GKRS hemorrhage or radiation-induced complication were treated before 1990; recent magnetic resonance imaging revealed a decrease in the size of the CM in three of these individuals and no size change in the other. The annual post-GKRS hemorrhage rate was 8% in this group. There was a trend in the hemorrhage rate to decrease 4 years postsurgery. There was also a trend for higher radiation doses administered to the periphery of the lesion to result in a lower risk of posttreatment hemorrhage. However, it could not be concluded whether GKRS affects the natural course of a CM. The incidence of radiation-induced complications was approximately seven times higher than that expected if the same number of patients had been treated by GKRS with the same radiation dose distributions for arteriovenous malformations instead of CMs.

CONCLUSIONS

The high incidence of radiation-induced complications does not seem to justify the limited protection the treatment may afford in only exceptional cases. A prospective randomized study is needed before the role of radiosurgery in the management of these lesions can be defined. Until such a study has proved differently, a caveat must be raised for the treatment of CM with GKRS.

Tumor suppressor p16INK4A: determination of solution structure and analyses of its interaction with cyclin-dependent kinase 4

The solution structure of the tumor suppressor p16INK4A has been determined by NMR, and important recognition regions of both cdk4 and p16INK4A have been identified. The tertiary structure of p16INK4A contains four helix-turn-helix motifs linked by three loops. Twelve tumorigenic mutants of p16INK4A have been constructed and analyzed for their structure and activity, and new mutants have been designed rationally. A fragment of 58 residues at the N terminus of cdk4 important for p16INK4A binding has been identified. The importance of this region was further verified by mutational analysis of cdk4. These results and docking experiments have been used to assess possible modes of binding between p16INK4A and cdk4.

Changes in motor performance in persons with Parkinson's disease after exercise in a mountain area

For one week in autumn, over a period of three consecutive years, a total of 12 persons with Parkinson's disease (PD) participated in daily walks of about 4 kilometers in a mountain area in Sweden in order to train rhythm, balance and coordination on the soft heaths. These persons were 60-78 years of age and had been found to be between stage 1 and stage 3 on the Hoehn and Yahr Staging Scale. The aim of the study was to find out whether a week of daily walks in the Swedish mountains would affect the motor performance of persons with PD, objectively and quantitatively assessed by a computer-assisted, opto-electronic movement analysis program, the Posturo-Locomotor-Manual (PLM) test. As compared with those before the journey, the results showed improved motor performance both immediately after the walking week and also at 3 but not 6 months later. The first year of participation showed the most pronounced improvements. The results demonstrate a long-lasting improvement in decreased movement time, indicating enhanced general motor performance and also an improved simultaneous index (SI), indicating a possible effect on the central nervous system. These findings, along with participants' narratives about what they did after returning home, may be indicative of strengthened self-confidence.

Tumor seeding following stereotactic biopsy of brain metastases. Report of two cases

In a series of 22 patients treated with gamma knife surgery for brain metastasis in whom biopsy specimens were obtained via stereotactically guided procedures before the radiosurgical treatment was administered, two cases with evidence of tumor seeding were observed on subsequent follow-up examination. These findings contradict the opinion that the risk for tumor spread after a biopsy is negligible. This evidence may be explained by the fact that radiosurgery leaves the surrounding tissue unaffected by the treatment, which results in preserved anatomy around the tumor. This allows the surgeon to define the previous biopsy channel and, consequently, whether a distant tumor recurrence may have resulted from tumor seeding related to the biopsy procedure. Additionally, radiosurgical treatment leaves tumor cells that may have been spread as a result of the biopsy unaffected, giving them the potential to divide and develop into a new tumor. In contrast to this, microsurgical removal of the tumor will affect the surrounding tissue, making it impossible to detect whether new metastases are resulting from seeding. Furthermore, conventional fractionated radiation therapy will sterilize tumor cells that may have spread, thus making it impossible for these cells to regrow. The authors conclude that the risk for tumor seeding following a stereotactically guided biopsy may be higher than previously assumed.

Construction of a standard reference for PET studies of methionine accumulation using a computerised brain atlas

Positron emission tomography (PET) is valuable for assessing the biochemistry and physiology of the human brain. A computerised brain atlas has been developed which allows demonstration of anatomical regions of PET images and manipulation of these images into a standardised anatomical space. Once the images are in this standardised three-dimensional space it is possible to make comparisons between individuals and groups of individuals. We describe the use of this atlas in the generation of a set of mean reference images using methionine PET images of normal volunteers.

Volume Determination of Intracranial Arteriovenous Malformations Prior to Stereotactic Radiosurgical Treatment

Exact dose planning for stereotactic radiosurgery was enabled in connection with diagnostic angiography or at the end of an endovascular procedure by simply placing a stereotactic localizing box onto the head of the patient while acquiring PA and lateral angiographic views.

The fiducials engraved on the localizing box enabled the appropriate images to be scaled to the stereotactic space. Regular dose planning was then performed after estimating the size of the patient's head. A prediction of the chances of obliteration and the risks of complication could then be made immediately after the endovascular or diagnostic procedure, and further therapy could be selected much more confidently.

This technique may also be used at centres without facilities for radiosurgical treatment if only the localizing box is available. The images may then be sent for evaluation to a unit with dose planning equipment.

The technique is simple and involves little risk, significantly improving patient management. Digital subtraction angiography was used in this study. A correction algorithm was used to minimize the geometric distortion inherent to the digital technique.

Sustained attention and awareness of disability in chronic neglect

The possible causative role of defective sustained attention and awareness of disability on the persistence of neglect was explored. The study included stroke patients who had had moderate or severe neglect 1-5 years before the start of the present examination. Questionnaire responses showed that the patients were aware of their disability. Impaired sustained attention was associated with poor performance in two out of three tests most sensitive in detecting neglect. This, together with indications of compensation on neglect tests, is interpreted as providing support for the hypothesis that chronic neglect is related to an impaired sustained attention.