Reliability of chest radiograph interpretation for pulmonary tuberculosis in the screening of childhood TB contacts and migrant children in the UK

AIM

To determine interobserver agreement between paediatric radiologists interpreting tuberculosis (TB) screening chest radiographs (CXR) in children in the UK, and the TB detection rate.

MATERIALS AND METHODS

A retrospective review was undertaken of electronic request, notes, and CXRs (>7 years) in children exposed to an infectious case of TB and new entrants to the UK, at a tertiary children's hospital. Included were those with positive Mantoux/interferon gamma release assay (IGRA), positive culture, or high clinical suspicion of TB. CXR reports were categorised as normal, abnormal without features of TB, or abnormal with features of pulmonary TB. Three paediatric radiologists from a dedicated paediatric radiology department evaluated available CXRs, aware of the TB screening indication, using a published CXR reporting tool and blinded to the initial CXR report and to each other. A majority decision was collated, and considered lymphadenopathy and miliary nodules as diagnostic of primary TB. Interobserver agreement was calculated using Cohen's kappa.

RESULTS

One hundred and forty-eight children underwent TB screening with a CXR. One hundred and twenty-five had available CXR reports and case notes, which indicated 20/125 (16%) had CXR features of TB. One hundred and twenty-one of the 125 had CXRs available to for panel review. Twenty of these 121 (17%) yielded a majority decision of pulmonary TB. Inter-reader agreement was moderate in all aspects (kappa 0.4-0.6).

CONCLUSION

The high percentage of pulmonary TB on CXR (16% original reports; 17% by panel review) suggests that it is worthwhile investigating childhood TB contacts; however, the routine use and recommendation for CXR is questionable because of only moderate interpretation reliability (kappa 0.5), even by experts.

Integrated spatial electron populations in molecules: The electron projection function

A "projection function," P(x,z), is defined as the partial integral of the molecular electron density, rho(x,y,z), over the region -infinity < y < +infinity. The projection provides a three-dimensional representation of molecular electron distributions. Chemically useful information can be discerned from graphical displays in either perspective plot or contour format. Numerical integration of the function gives the integrated spatial electron population for any region of interest. The use of the projection function and difference functions is exemplified by application to acetaldehyde.

Case report of a Wilms' tumor and a left-sided inferior vena cava. A common tumor with a normal variant of surgical significance

We report a case of a successful surgical resection of a Wilms' tumor in the right kidney with a coincidental preoperative imaging finding of a left-sided inferior vena cava. To our knowledge, these 2 conditions occurring together has not been previously reported in literature. Diagnostic features and the value of magnetic resonance imaging are emphasized. We also review the literature of major venous anomalies and their influence on surgical procedures carried out on such patients.

Sub-aponeurotic fluid collections in infancy

AIM

To describe the radiological features and natural history of sub-aponeurotic fluid collections presenting after the neonatal period.

MATERIALS AND METHODS

All cases of sub-aponeurotic scalp fluid collection presenting to the radiology department between June 1996 and June 2000 were reviewed. Note was made of the birth history, the radiographic and ultrasound features and the natural history (including any treatment) of the collection.

RESULTS

Seven cases of sub-aponeurotic fluid collections were identified. There were six infants who presented 3.5-18 weeks (mean nine weeks) after delivery, four of whom had had ventouse-assisted delivery. The last case was in a seven-year-old child who presented one month after minor head trauma. Clinical examination revealed non-tender, soft, mobile and fluctuant scalp swellings in all patients. Ultrasound identified sonolucent fluid collections of between 5 and 24 mm depth in the sub-aponeurotic space. No skull fractures were identified. Six patients were treated conservatively and one had fluid aspirated and a compression bandage applied. All cases resolved 2-24 weeks after diagnosis and there were no long-term sequelae.

CONCLUSION

Sub-aponeurotic scalp collections presenting after the neonatal period are usually associated with ventouse-assisted delivery ultrasound is useful for diagnosis. The condition is benign and resolution occurs with conservative treatment.

Pneumatic dilatation for childhood achalasia

Treatment of achalasia by pneumatic balloon dilatation (PBD) is well established in adults. Due to limited experience and the rarity of the condition in children, there are relatively few reports in the paediatric literature. Although PBD has been reported as a primary method of treatment, there are no reports of secondary PBD for childhood achalasia. Between 1995 and 1999, five patients underwent treatment for achalasia (age: 9-14 years, M:F = 4:1). The presenting symptoms were dysphagia (5). vomiting episodes (2), aspiration (1), food-bolus obstruction (1), and failure to thrive (1). In all patients a barium swallow and manometry were used to confirm the diagnosis. Three underwent primary PBD. Two who had previously undergone surgical myotomy underwent secondary PBD for recurrence of symptoms. Dilatation was performed using a 35-mm balloon with the child under general anaesthesia. Technical success was defined as demonstration of a waist under screening at lower pressures followed by abolition of the waist at higher pressures. In addition to reviewing our results, a systematic review of the literature was performed (Medline, Cochrane Library, Pubmed, Embase). Three patients (primary dilatation) showed excellent improvement after a single dilatation. In two cases (secondary dilatation) three and five attempts were required. No complications were encountered. The mean follow-up period was 2 years (1-3.5 years) and four patients remained asymptomatic, an overall success rate of 80%. The literature review revealed similar good results in most of the recent reports. Thus, PBD as a primary treatment for childhood achalasia has a success rate of 70%-90% with minimal side effects, short hospital stay, and good patient acceptability over an operation. We have also established the usefulness of this method as a secondary treatment when symptoms recur after surgery.

Mixed foregut cyst associated with esophageal atresia

The authors report an unusual case of a thoracoabdominal foregut malformation with components of bronchogenic, esophageal duplication, and pancreatic enterogenous cysts, that presented in a child with esophageal atresia. J Pediatr Surg 36:939-940.

Outcome and clinical course of 100 patients with adenovirus infection following bone marrow transplantation

We conducted a retrospective review of the clinical features and outcome of adenovirus infection in 572 consecutive patients transplanted in a single centre over a 10 year period. One hundred patients (17%) had a total of 105 episodes of adenovirus infection diagnosed at a median of 18 days post transplant (range 2-150 days). The incidence was higher in children than adults (21% vs 9%, P < 0.001) and in unrelated donor vs matched sibling donor transplants (26% vs 9%, P < 0.001). Diarrhoea and fever were the most common presenting features. Reflecting these symptoms, the most common site of isolation was the stool. Serotypes 1, 2 and 7 were the most frequently seen (total of 41/68 or 60% of evaluable cases). In six patients (6%) adenovirus infection was the direct cause of death occurring at a median of 72 days post transplant (range 18-365 days). Five of these six patients had pulmonary involvement and four had associated graft-versus-host disease (GVHD). Three further patients were considered to have severe adenoviral disease (total incidence 9%). Isolation of virus from multiple sites correlated with a poor outcome (P < 0.001). Comorbid viral infection was common in this group with 50% of all patients having other viruses isolated (predominantly polyoma virus and cytomegalovirus). We conclude that adenovirus is commonly isolated after bone marrow transplant and is a cause of significant morbidity but was a rare cause of mortality (6/572 = 1%) in our patient group as a whole. The relative infrequency of severe infection will make it difficult for the transplant physician to decide which patients should receive experimental antiviral drugs such as ribavirin and cidofovir or immunomodulatory therapy with donor white cell infusions.

The outcome of 26 patients with respiratory syncytial virus infection following allogeneic stem cell transplantation

Respiratory syncytial virus (RSV) is known to cause acute lung injury in the immunocompromised host, especially recipients of bone marrow allografts. Specific prognostic factors for the development of severe life-threatening disease remain to be identified as does the optimum treatment of established disease. Over a 5-year period the incidence and outcome of RSV in BMT recipients was analysed retrospectively. Prognostic factors assessed included type of transplant, engraftment status at the time of infection, the presence of lower respiratory tract disease, viral genotype and treatment received. During the study period, 26 of 336 (6.3%) allogeneic stem-cell recipients were identified as having RSV. Five patients (19.2%) died as a direct result of RSV. One patient died secondary to an intracranial bleed with concomitant RSV. There were four patients with graft failure (two primary and two secondary) attributable to the presence of RSV, two of whom subsequently died of infections related to prolonged myelosuppression. The presence of lower respiratory tract infection and a poor overall outcome was the only statistically significant association. Unrelated donor transplants and AML as the underlying disease appeared to be associated with a poorer outcome. Engraftment status, viral genotype and RSV treatment received did not correlate with outcome. We conclude that future studies are required to identify early sensitive and reproducible prognostic factors of RSV in the immunocompromised host. The roles of intravenous and nebulised ribavirin need to be clarified by prospective controlled trials.

The use of play therapy in the preparation of children undergoing MR imaging

Magnetic resonance (MR) imaging has become an important technique in the evaluation of a wide range of congenital and acquired conditions in children. The ability to image in multiple anatomic planes without the use of ionizing radiation has particular advantages. However scan times can be long, and the narrow bore and noise generated by most units make the procedure very intimidating to the young child. The use of surface coils may exacerbate this, often necessitating recourse to sedation or anaesthesia. We describe a technique involving play therapy which we have found useful in the preparation of young children for MR imaging and which has reduced the number of non-diagnostic scans and the need for sedation or anaesthesia.

Technetium-99m-HMPAO labelled leucocytes in the detection and monitoring of inflammatory bowel disease in children

This study was a retrospective evaluation of the use of technetium-99m hexamethylpropyleneamineoxime (HMPAO) labelled leucocytes in the investigation of suspected inflammatory bowel disease in children. The images were analysed in 35 children and the findings were compared with the results of endoscopy/biopsy, barium studies and antinuclear cytoplasm antibody (ANCA) serology. The sensitivity of the white cell scan was 83% and the specificity 81%. This compares well with other studies in adults and is superior to barium investigations. The technique is recommended as a first line investigation to detect inflammatory bowel disease with a resultant reduction in the use of endoscopy and barium imaging.

Detection of bone lesions in Langerhans cell histiocytosis: complementary roles of scintigraphy and conventional radiography

PURPOSE

This research was undertaken to determine the relative sensitivity of scintigraphic and radiographic bone survey examinations in detecting bone lesions in various regions of the skeleton in patients with a histopathologic diagnosis of Langerhans cell histiocytosis (LCH).

PATIENTS AND METHODS

Radionuclide skeletal scintigraphy (RNSS) and x-ray skeletal surveys (XRSS) of 42 children with a histopathologic diagnosis of LCH were evaluated retrospectively.

RESULTS

Of the 191 lesions detected in 42 patients, 36 (19%) were missed on RNSS and 55 (29%) were missed on XRSS. Most of the missed lesions on RNSS were in the skull (26 of 36). XRSS also missed 13 skull lesions seen on RNSS. Most of the lesions missed on XRSS were in the ribs (20 of 30 rib lesions), whereas RNSS identified 29 of them. XRSS also missed 13 of 38 lesions in the spine and pelvis, while RNSS demonstrated all of them. Both modalities showed comparable sensitivity in the extremities.

CONCLUSION

RNSS has a greater value in detecting sites of bone involvement with LCH than reported previously. RNSS is more sensitive than XRSS in detecting histiocytic lesions in the ribs, spine and pelvis and less sensitive in identifying lesions in the skull.

Fatigue fractures of the sacrum in children: two case reports and a review of the literature

We present the clinical and radiological features of two children with fatigue fractures of the sacrum. Both patients were active, had no underlying bone disease and presented with insidious onset of low back pain. Plain radiography was non-contributory to the diagnosis. In both patients a focal area of increased activity was present in the lateral aspect of the sacrum on bone scintigraphy, which corresponded to linear medullary sclerosis in the sacral ala demonstrated by computed tomography. Magnetic resonance imaging in one patient revealed a linear signal void in the sacral ala on T1- and T2-weighted images. This was surrounded by diffuse low marrow signal on T1-weighted images, and increased marrow signal on T2-weighted images. Fatigue fractures of the sacrum should be considered in the differential diagnosis of low back pain in children. An awareness of their appearance on magnetic resonance imaging is important as this modality is increasingly utilised, particularly in children.

Osteomyelitis in hospitalized children with chickenpox: imaging findings in four cases

OBJECTIVE

The most common complications of chickenpox are skin and soft-tissue infections. Pneumonia and CNS involvement occur less often, and skeletal complications are considered rare. The purpose of this study was to evaluate the imaging findings of osteomyelitis in children after chickenpox.

MATERIALS AND METHODS

We retrospectively reviewed the records of children admitted to our institution because of chickenpox and analyzed the imaging findings in those who had skeletal involvement. Ninety-seven patients were admitted between January 1991 and January 1993 because of chickenpox or a complication thereof. Four previously healthy patients, three boys and one girl, between 1 and 6 years old had osteomyelitis. Staphylococcus aureus was isolated from bone in one patient, and group A beta-hemolytic streptococcus was isolated from blood cultures in another. No organism was grown in the other two; necrotic bone was recovered from one lesion and the other healed with periosteal formation of new bone typical of osteomyelitis. All patients were treated with IV antibiotics, and their recoveries were uncomplicated.

RESULTS

Conventional radiographs showed loss of fat planes in three patients and destruction of bone in two. Bone scintigraphy showed increased uptake of radionuclide in early and late phases in three patients. Uptake in one case was extensive, with a central area of relatively little uptake corresponding to a subperiosteal fluid collection. CT in two and MR imaging in one showed subperiosteal fluid collections surrounding the involved bones in association with bone and marrow changes.

CONCLUSION

Osteomyelitis was the fourth most common complication of chickenpox in our series. The appearances on conventional radiographs and scintigrams are indistinguishable from those of typical bacterial osteomyelitis. However, CT and MR imaging showed subperiosteal fluid collections in three of four patients, an appearance only occasionally seen with typical osteomyelitis.

Complications in percutaneous transluminal angioplasty: relationships with patient age

Five hundred consecutive attempted lower limb angioplasties for ischaemic disease (370 patients, mean age 65.6 years, range 33-91 years) were reviewed. Significant complications occurred in 44 cases (8.8%). Nine patients (1.8%) underwent emergency surgery related to a complication. A further 12 patients (2.4%) underwent elective surgery related to a complication. In addition, four patients died within 30 days of the procedure; one following surgery performed because of a complication of angioplasty, one following a myocardial infarction, one following severe bleeding associated with subsequent thrombolytic therapy and one during emergency surgery related to a complication of angioplasty. A correlation was found between complication rate and age. This relationship was independent of the approach to, the position of, and the severity of the treated lesion. Elderly patients are at increased risk of complication in lower limb angioplasty.

Chest radiographs after permanent pacing. Are they really necessary?

The chest radiographs of 600 consecutive patients undergoing insertion of a permanent cardiac pacemaker were reviewed to determine the incidence and nature of abnormalities present. Abnormalities were detected on the chest radiographs of 131 patients (21.8%). Unsatisfactory electrode tip position and other features related to the electrode wire were commonest (14.4%). Complications related to the lungs and pleura were present in 5.5%, and those related to the generator and pouch least frequent (1.9%). Complications occurred more frequently following installation of a replacement system (48.3%) compared to new systems (17.2%). Important complications not initially detected included pneumothorax (8/15) and poor electrode loop (26/27). Chest radiographs following permanent cardiac pacing frequently demonstrate significant abnormalities whose detection is improved by awareness of their incidence and nature.

Percutaneous femoral artery puncture: practice and anatomy

In a survey of the superficial landmarks used to select the site of puncture of the femoral artery for angiography, the inguinal skin crease was most popular, preferred by 39.2% of angiographers. The maximal femoral pulse irrespective of the position of the skin crease was the next most popular landmark (24.7%). Bony landmarks were least popular (13.0%). The majority (73.7%) of those using the skin crease punctured at the same level or distal to it. The relationship of these superficial landmarks to the common femoral artery (CFA) and its bifurcation were investigated. The inguinal skin crease was distal to the bifurcation of the CFA in 71.9% of limbs (mean, 0.61 cm). The maximal femoral pulse was over the CFA in 92.7% of limbs, and the CFA was projected over the medial aspect of the femoral head in 77.9% of limbs. The use of the inguinal skin crease is a popular though unreliable guide for puncture of the CFA. Use of the maximal femoral pulse will enable more constant puncture of the CFA.

Interaction specificity of the anthracyclines with deoxyribonucleic acid

The interaction specificity of salmon sperm DNA with various derivatives of daunorubicin has been studied. The results of binding, viscometric, 1H nuclear magnetic resonance (NMR), flow dichroism, DNA template inhibition, rates of dissociation, and circular dichroism studies are found to be consistent with an intercalation mode of binding of the anthracycline ring as has been shown by other investigators. Moreover, it is observed that (i) strength of binding, (ii) the ease of dissociation of DNA-anthracycline complexes, and (iii) the degree of inhibition of the DNA-dependent RNA polymerase are dependent on the presence of the amino sugar moiety of daunoseamine. The results are consistent with specific H bonding of the amino group of the sugar moiety with DNA as has been suggested earlier by Pigram et al. (Pigram, W.J., Fuller, W., and Hamilton, L.D. (1972), Nature (London), New Biol. 235, 17). Peptide derivatives substituted at the amino sugar function of daunorubicin lower the affinity of the drug to DNA and presumably interfere with the "full insertion" of the anthracycline drugs between base pairs of DNA. The significance of these findings in relation to the biological efficacy of daunorubicin and related derivatives as antileukemic agents is discussed.

Sturcture-activity relationship of daunorubicin and its peptide derivatives

The synthesis of potentially specific antitumor peptide derivatives of daunorubicin is presented. The interaction specificites of the drugs with nucleic acids have been examined via stop-flow kinetics as well as the inhibition of DNA template activity. It is found that the biological activity of the daunorubicin derivatives against the mouse P388 tumor is directly proportional to RNA polymerase inhibition and inversely proportional to the rate of dissociation of the DNA complex. It is concluded that the biological efficacy of drugs which act at the replicative and transcriptional level may be estimated by the more rapid in vitro techniques provided that problems of permeability, solubility, stability, etc., in vivo are not encountered.