Benjamin Z. Koplewitz

Added Value of SPECT/CT for Correlation of MIBG Scintigraphy and Diagnostic CT in Neuroblastoma and Pheochromocytoma

OBJECTIVE In pheochromocytoma and neuroblastoma, pathologic findings on metaiodobenzylguanidine (MIBG) scintigraphy (planar and SPECT) and on diagnostic CT are sometimes difficult to correlate. Furthermore, CT reading may be impaired by anatomic distortion after surgery or irradiation and if contrast agent is not injected. The present study evaluates the impact of SPECT/CT fusion images on correlation and image analysis of both techniques. MATERIALS AND METHODS Eleven patients, three adults (age range, 27-64 years) with pheochromocytoma and eight children (age range, 16-72 months) with neuroblastoma, underwent 15 (123)I-MIBG scintigraphy (whole body and SPECT/CT) and diagnostic CT during follow-up after treatment, with a time interval of 2 to 30 days (mean, 12 days) between MIBG scintigraphy and diagnostic CT. The diagnostic CT scans were read twice: blindly and with knowledge of the SPECT/CT findings. The scintigraphic and anatomic data were subsequently compared and were verified by clinical outcome. RESULTS Of 15 imaging studies, there were nine cases of discordance between SPECT/CT and diagnostic CT, whereas concordant findings of planar MIBG and diagnostic CT were observed in six studies. Overall, SPECT/CT provided additional information in eight of the 15 cases (53%) and in eight of nine discordant studies (89%). In one case of pheochromocytoma in which anatomy was distorted by previous surgery and contrast agent was not injected, SPECT/CT findings guided the diagnostic CT that had initially misinterpreted the right adrenal gland as the inferior vena cava. In three of 11 studies performed for neuroblastoma, SPECT/CT facilitated the diagnostic CT reading: in one study, a small paravertebral thickening was overlooked at blind CT reading and in another case, SPECT/CT localized and characterized a soft-tissue mass medial to the iliac bone, which was missed on diagnostic CT in an area of difficult differential anatomy (bowel loops and eventual involved lymph nodes). In the third case, SPECT/CT directed the diagnostic CT to the MIBG abnormality after multiple surgical procedures. In these four cases, MIBG SPECT/CT allowed for localization of the pathologic site that was difficult to visualize on diagnostic CT. In four additional neuroblastoma studies in which a residual mass was present on diagnostic CT, planar MIBG scintigraphy was negative. SPECT/CT, focused on the area of the diagnostic CT abnormality, showed no focal MIBG uptake, thus increasing the diagnostic certainty of remission. CONCLUSION In cases of equivocal diagnostic CT, SPECT/CT bridges the gap between MIBG scintigraphy and diagnostic CT, with guidance of the diagnostic CT and characterization of its findings. In this small series, MIBG SPECT/CT increased the diagnostic certainty in 89% of discordant studies.

Traumatic diaphragmatic injuries in infants and children: imaging findings

Objectives. Traumatic diaphragmatic injuries (DI) in infants and children are uncommon and are often associated with multiple severe injuries. Delayed presentation can be life threatening due to organ herniation and strangulation. We present the imaging findings in a relatively large population of children who experienced this rare injury.¶Methods. Medical records of all patients admitted to our Trauma Service from 1977 to 1998 with DI were retrospectively reviewed recording imaging, clinical and surgical or autopsy findings.¶Results. Of sixteen patients with DI (7 females, 9 males; age 3 weeks to 15 years), 14 suffered from blunt trauma secondary to high-energy impact, and 2 from penetrating injuries. Unilateral DI occurred equally on each side, with one bilateral injury. Associated injuries, present in 81 %, included severe head injuries, visceral, mesenteric and vascular injuries and multiple fractures. Six patients died from multiple organ failure (3), head injury (2), and shock (1). Findings in the initial chest X-ray suggested the diagnosis in 13 (81 %) of 16 injuries, and CT demonstrated irregularity and thickening of the diaphragm in 4 out of 7.¶Conclusions. Plain film findings suggested the diagnosis in most; CT and MR were useful adjuncts. High index of suspicion and awareness of the mechanism of injury can lead to prompt diagnosis, early repair, and decreased morbidity and mortality.

Ankylosis of the temporomandibular joint as a sequela of septic arthritis and neonatal sepsis.

Ankylosis of the temporomandibular joint (TMJ) can be a result of trauma, degenerative changes and infection or of a space-occupying lesion and, when occurring during early childhood, can result in severe functional disability and facial distortion. Septic arthritis of the TMJ is extremely rare in young infants. We report two children with TMJ ankylosis that is believed to have been a consequence of undiagnosed septic arthritis of the TMJ in the neonatal period.

Perivascular epithelioid cell tumor of the ascending colon mesentery in a child: case report and review of the literature

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor. Perivascular epithelioid cell tumors of the gastrointestinal tract are very rare, with only about 20 previous reported cases. We present a 5.5-year-old boy with PEComa of the right colon. Treatment consisted of tumor resection only, without additional adjuvant therapy. Two years after surgery, he remains free of tumor. To the best of our knowledge, this is the youngest reported child with PEComa of the colon. We review the literature concerning PEComas in children, especially those of the gastrointestinal tract. We emphasize the importance of correct immunohistochemistry diagnosis, recommended treatment, and surveillance of this unique family of tumors.

Prevention of esophageal strictures in a caustic burn model using halofuginone, an inhibitor of collagen type I synthesis

Objective: Esophageal strictures caused by caustic injury continue to be a plaguing problem. Halofuginone (HF) has been proven to inhibit the formation of fibrosis in various animal models and human diseases. Its mechanism appears to be through the suppression of the production of collagen α1(I) and transforming growth factor‐β signaling pathway. We tried to assess whether HF would have an effect on the formation of strictures after inducing caustic esophageal.

An outbreak of adenovirus type 7 in a residential facility for severely disabled children.

Background: Adenoviruses cause a variety of clinical symptoms, involving the respiratory, gastrointestinal, urogenital, and neurologic systems. Only a few of the 55 known serotypes of adenovirus that affect humans can cause outbreaks of respiratory tract infection. Aim: To describe the characteristics and clinical manifestations of severe respiratory disease contracted by 8 physically and cognitively disabled children during a very short outbreak of adenovirus serotype 7 infection in a residential facility. Methods: The clinical, imaging, and laboratory findings of the patients who were hospitalized with severe respiratory symptoms were retrospectively reviewed. Molecular typing of the adenovirus was performed. Results: During 10 days in February 2010, 8 severely disabled children, 9 months to 5 years of age (median 22.5 months), from the same residential facility, were hospitalized due to severe acute respiratory disease with hypoxemia. Four of them (50%) needed mechanical ventilation for 2 to 8 days and one developed multisystem failure, including acute renal failure. Adenovirus serotype 7 was detected in the respiratory specimens of all 8 children. Two patients were treated with intravenous cidofovir. All 8 patients survived and were discharged after hospitalization of 6 to 15 (median: 11.5) days. The epidemiologic investigation revealed that all the 8 affected children shared a playroom and a caregiver worked with them while suffering fever, sore throat, and conjunctivitis before the onset of the outbreak. Conclusions: Adenovirus type 7 may cause short outbreaks of infection in institutions, causing children to develop life-threatening disease. Early detection of pathogens causing respiratory infections in institutions, isolation, and other preventive precautions are advocated. Moreover, vaccination of health care providers in institutions with the currently available live, oral adenovirus vaccine for types 4 and 7 should be considered.

The lateral view: a useful adjunct in the diagnosis of malrotation

Sir, I thoroughly enjoyed Dr. Guido Currarinos article [1] and your editorial comment. The simple form of cervical lung protrusion can persist into adulthood and be observed as an incidental finding. I recall two separate specific instances when this simple form was the explanation of an unusual complication. During my general radiology training and before entering into pediatric radiology, I was carrying out a neuroradiologic procedure of a direct puncture carotid angiogram. In those days that was the routine practice, and catheter angiography was just being introduced. Certainly there were no computed tomography, magnetic resonance imaging, or Doppler ultrasound facilities in those aearlyo days of interventional/neuroradiology. On two separate occasions after direct puncture of the common carotid artery low in the neck, each patient developed a small apical pneumothorax subsequent to withdrawal of the cannula. This was an unusual experience for me, and on investigation the explanation of this rare complication was that both adults had cervical lung protrusions, and the needle had knicked the pleura on entering the carotid artery. None of them required drainage of small pneumothorax, which resolved spontaneously in due course. I have not come across this particular complication since in my adult or long pediatric practice.

Truncating Mutation in the Nitric Oxide Synthase 1 Gene Is Associated With Infantile Achalasia

Nitric oxide is thought to have a role in the pathogenesis of achalasia. We performed a genetic analysis of 2 siblings with infant-onset achalasia. Exome analysis revealed that they were homozygous for a premature stop codon in the gene encoding nitric oxide synthase 1. Kinetic analyses and molecular modeling showed that the truncated protein product has defects in folding, nitric oxide production, and binding of cofactors. Heller myotomy had no effect in these patients, but sildenafil therapy increased their ability to drink. The finding recapitulates the previously reported phenotype of nitric oxide synthase 1-deficient mice, which have achalasia. Nitric oxide signaling appears to be involved in the pathogenesis of achalasia in humans.

Successful treatment of progressive stage 4s hepatic neuroblastoma in a neonate with intra-arterial chemoembolization

Stage 4s neuroblastoma (NB) is a unique entity seen in infants less than 1 year of age, with metastatic disease confined to liver, skin, or bone marrow. Despite metastatic spread, stage 4s NB has a favorable outcome. An exception to this is seen in neonates who present with progressive enlargement of the liver with secondary respiratory compromise and liver failure. We describe a 4‐week‐old neonate who presented with 4s NB, with a rapidly enlarging liver, resulting in respiratory and hepatic failure, who had a rapid, sustained, and ongoing response to chemoembolization of the hepatic artery. This approach is feasible at this age, and may be effective in improving the outcome in this group of patients.

Factors associated with bacteremia in young infants with urinary tract infection.

Background: Urinary tract infection (UTI) is the most frequent severe bacterial infection in infants. Up to 31% of infants with UTI have bacteremia. Methods: We retrospectively identified all infants aged 0–2 months who were managed in our hospital with UTI during a 1-year period. Those with bacteremia were compared with those without bacteremia, according to the following variables: ethnicity, age, gender, white blood cell and polymorphonuclear counts, C-reactive protein, urinalysis and blood creatinine values as related to age-appropriate norms, imaging and outcome. Results: We identified 81 infants with 82 episodes of UTI. Most occurred in males (72.8%) and 35 (42.7%) were in infants of non-Jewish origin. In 14/81 (17.3%) of episodes, Escherichia coli was cultured from blood. In multivariate analysis, increased blood creatinine levels (P = 0.004) and non-Jewish origin (P = 0.006) were associated with bacteremia. Time to defervescence was significantly longer in bacteremic versus nonbacteremic children (P = 0.018). Duration of hospitalization was longer in bacteremic infants—10 (7–17) days in bacteremic versus 7 (1–14) days in nonbacteremic children (P < 0.001). Conclusions: In infants aged 0–2 months with UTI, increased blood creatinine value at admission was associated with bacteremia. This value provides an additional clue on admission, independent of personal judgment, to help identify infants at higher risk for bacteremia, prolonged hospitalization and possible complications.