Ultrasonographic Findings of the Penguin's Beak Sign in Neonates With Anorectal Malformation.

In the ultrasound for anorectal malformation, penguin's head represents distal rectal pouch, and its beak runs toward distal side of fistula. Despite the rarity of this disease and insufficient ultrasound experience of the examiner, this sign is useful for ultrasound examiners to accurately diagnose the type of anorectal malformation.

Sonographic Differentiation From Pseudoureterocele of Ectopic Ureter and Ureterocele in Pediatric Patients.

OBJECTIVES: Ectopic ureter and ureterocele need an adequate treatment plan and different surgical interventions. However, some cases appear as intravesical cystic lesions on ultrasound, with ectopic ureter sometimes reported as pseudoureterocele. This study aimed to describe the sonographic imaging findings of intravesical cystic lesions to differentiate between pseudoureterocele and ureterocele. METHODS: Nineteen patients with duplex collecting system and intravesical cystic lesions that were classified into pseudoureterocele and ureterocele based on the surgical findings were included. The ultrasound findings compared between the 2 groups were as follows: intravesical lesion with/without a covered muscular layer, presence/absence of notch sign within the lesion, and dynamic change in the appearance of intravesical cystic lesions using Fisher's exact test. RESULTS: The lesions in 3 patients were classified as pseudoureterocele due to ectopic ureter and the remaining 16 as ureterocele. Significant differences were observed in intravesical lesions with/without a muscular layer (pseudoureterocele versus ureterocele = 3/0 versus 3/13, P = .021) and the presence or absence of a notch sign within the vesical cystic lesion (pseudoureterocele versus ureterocele = 3/0 versus 3/13, P = .021) between the groups. Although there was a tendency for the dynamic change in the appearance of intravesical cystic lesions to be more detectable in cases with ureterocele than in pseudoureterocele, the difference was not significant (0/3 versus 11/5, P = .058). CONCLUSIONS: Sonographic findings, including bladder muscular layer location and the presence of a notch sign within the cystic lesion, were useful in differentiating pseudoureterocele and ureterocele in intravesical cystic lesions in pediatric patients with a duplex collecting system.

Sonographic findings associated with complications in pediatric patients with septic arthritis.

OBJECTIVES: Ultrasound is a valuable tool for diagnosing septic arthritis and guiding the development of treatment plans. This study aimed to identify sonographic findings associated with complications in septic arthritis. METHODS: Twelve patients aged <5 years diagnosed with septic arthritis were classified into two groups: those with and without complications. Complications were defined as the destruction of the epiphyseal bone head and metaphysis bone cortex. The following sonographic findings were compared between the two groups using Fisher's exact test: synovial membrane thickness, joint effusion, diminished hyperechoic foci within the epiphyseal bone head, and diminished smooth metaphyseal bone cortex. RESULTS: Overall, 4 of 12 patients developed complications. Joint effusion and synovial membrane thickening were detected in all patients with septic arthritis. The incidence of diminished hyperechoic foci within the epiphyseal bone head was significantly different between the two groups (presence/absence in patients with complications vs. without = 3/1 vs. 0/8, p = 0.018). The incidence of diminished smooth metaphyseal bone cortex was higher in patients with complications than in those without; however, this difference was not statistically significant (presence/absence in patients with complications vs. without = 4/0 vs. 3/5, p = 0.081). CONCLUSION: Ultrasound proved to be an effective diagnostic tool for septic arthritis and also demonstrated its potential in predicting complications of septic arthritis in the pediatric population.

The burrower bug Macroscytus japonensis (Hemiptera: Cydnidae) acquires obligate symbiotic bacteria from the environment.

Many plant-feeding stinkbugs belonging to the infraorder Pentatomomorpha possess a specialized symbiotic organ at the posterior end of the midgut, in which mutualistic bacterial symbionts are harbored extracellularly. In species of the superfamily Pentatomoidea, these symbionts typically are verticallytransmitted from host mothers to offspring, whereas in species of the superfamilies Coreoidea and Lygaeoidea they are acquired from the environment. In the pentatomoid family Cydnidae, vertical symbiont transmission has been reported in several species. Here, we report the first case of environmental symbiont acquisition in Cydnidae, observed in the burrower bug Macroscytus japonensis. A comprehensive survey of 72 insect samples from 23 sites across the Japanese archipelago revealed that (1) symbionts exhibit remarkably high diversity, forming six distinct phylogenetic groups within the Enterobacteriaceae of the γ-Proteobacteria, (2) most symbionts are cultivable and closely related to free-living Pantoea-allied bacteria, and (3) symbiont phylogenetic groups do not reflect the host phylogeny. Microbial inspection of eggs revealed the absence of bacteria on the egg surface. These results strongly suggest that symbionts are acquired from the environment, not vertical transmission. Rearing experiments confirmed environmental symbiont acquisition. When environmental symbiont sources were experimentally withheld, nymphs became aposymbiotic and died before molting to the second instar, indicating that nymphs environmentally acquire symbionts during the first-instar stage and that symbionts are essential for nymphal growth and survival. This study highlights Cydnidae as the only pentatomoid family that includes species that environmentally acquire symbionts and those that vertically transmit symbionts, providing an ideal platform for comparative studies of the ecological and environmental factors that influence the evolution of symbiont transmission modes.

Subsequent Complications of Pediatric Patients With Osteomyelitis and Accompanying Subperiosteal Abscess.

BACKGROUND: Subperiosteal abscesses (SAs) are a complication of osteomyelitis that requires surgical intervention. This study aimed to characterize the occurrence of subsequent complications in pediatric patients with osteomyelitis and accompanying SA. METHODS: Fourteen pediatric patients with SAs were included. We recorded clinical information, including age at diagnosis, interval (days) between the onset of symptoms and diagnosis, location of SAs (long/flat bone), pathogens [methicillin-resistant Staphylococcus aureus (MRSA)/non-MRSA], treatment period (days) and any subsequent complications. Patients were classified based on SAs with or without complications. Mann-Whitney U and Fisher exact tests were used for statistical analyses, and data are expressed as median and interquartile range. RESULTS: Six patients (42.9%) had subsequent complications. There were significant differences in location of SAs between these two groups (long/flat bone, with versus without complication = 6/0 versus 3/5; P = 0.031). No significant differences were observed between the groups in terms of age [with versus without complication = 13.8 (9.7-24.5) versus 556.3 (5.0-107.8) months; P = 0.491], the interval (days) between symptoms onset and diagnosis [with versus without complications = 5 (1-10) versus 5 (3-6.5) days; P = 0.950], pathogenesis (MRSA/non-MRSA, with versus without complication = 4/2 versus 2/6; P = 0.277) and treatment period [with versus without complication = 50.5 (31-57) versus 29 (24.5-41.5) days; P = 0.108]. CONCLUSIONS: Pediatric patients with SAs in the long bones have a higher likelihood of experiencing subsequent complications than those with SAs in flat bones. Physicians should carefully manage this vulnerable patient group.

Imaging Diagnosis for Intradiaphragmatic Pulmonary Sequestration: A Pilot Study.

OBJECTIVES: Extrapulmonary sequestration (EPS) within the diaphragm (ID-EPS) is rare and requires additional procedures such as incision or detachment of the diaphragm from the lesion for diagnosis. This study aimed to describe the imaging findings and evaluate the diagnostic accuracy of ultrasonography and computed tomography (CT) for ID-EPS. MATERIAL AND METHODS: Split diaphragm sign, shape of lesion edge, drainage vein into intra-abdomen on ultrasound and CT, and lesion characteristics on ultrasound were compared between patients with ID-EPS and with above-diaphragm EPS (AD-EPS) using Fisher's exact test. RESULTS: Three and nine patients were diagnosed with ID-EPS and AD-EPS, respectively. Significant differences were observed between the two groups in the split diaphragm sign on ultrasound (presence/absence in patients with ID-EPS vs AD-EPS, 2/1 vs 0/9, P = .046), shape of lesion edge on ultrasound/CT (round/beak in patients with ID-EPS vs AD-EPS, 3/0 vs 0/9, P = .005 on both CT and ultrasound), lesion characteristics on ultrasound (presence/absence of cystic area within lesion in patients with ID-EPS vs AD-EPS, 0/3 vs 7/2, P = .046), and the drainage vein into the abdomen on CT (presence/absence in patients with ID-EPS vs AD-EPS; 2/1 vs 0/9, P = .046). No drainage veins were visualized in the abdomen on ultrasonography and no significant differences in the presence/absence of the split-diagram sign on CT (presence/absence in patients with ID-EPS vs AD-EPS and ID-EPS; 0/3 vs 0/9, P > .999; 1/2 vs 0/9, P = .250) were observed between the two groups. CONCLUSION: A combination of postnatal ultrasonography and CT was useful in predicting EPS located within the diaphragm.

Booster administration of Tc-99m PMT for delayed static imaging in patients with biliary atresia.

OBJECTIVE: Tc-99m N-pyridoxyl-5-methyl-tryptophan (PMT) hepatobiliary scintigraphy has high diagnostic performance for biliary atresia. Our hospital implements standard Tc-99m PMT administration followed by a 6 h static imaging review; booster doses are given in cases requiring 24 h delayed scans. This study aimed to evaluate the diagnostic performance of this method. METHODS: A total of 37 pediatric patients who underwent Tc-99m PMT biliary scintigraphy were classified into the surgically-diagnosed biliary atresia or non-biliary atresia groups. The absence of tracer accumulation in the small bowel was considered a hepatobiliary scintigraphic diagnosis of biliary atresia. The Clopper-Pearson method was used to calculate the 95% confidence intervals (CIs) for determining the diagnostic accuracy, negative predictive value, positive predictive value, sensitivity, and specificity of Tc-99m PMT biliary scintigraphy. RESULTS: Among the 37 patients, 12 were classified into the diagnosis of biliary atresia group. Regarding biliary scintigraphy findings, 16 of 37 patients demonstrated tracer accumulation in the small bowel within 6 h of testing. These cases were diagnosed as non-biliary atresia, requiring no further testing or booster administration. In contrast, 21 patients underwent delayed testing requiring booster administration, which revealed 13 without tracer excretion and 11 who were diagnosed with biliary atresia. Among the eight patients with tracer accumulation, only one was diagnosed with biliary atresia. Furthermore, two cases without tracer excretion and seven cases with tracer excretion were clinically diagnosed as non-biliary atresia. The diagnostic performance of our examination was as follows: a diagnostic accuracy of 91.9% (34/37; 95% CIs 78.0-98.3%), sensitivity of 91.6% (11/12; 95% CIs 61.5-99.8%), specificity of 92.0% (23/25; 95% CIs 74.0-99.0%), a positive predictive value of 84.6% (11/13; 95% CIs 54.6-98.0%), and a negative predictive value of 95.8% (23/24; 95% CIs 78.9-99.9%). CONCLUSIONS: Our protocol for Tc-99m PMT biliary scintigraphy using tracer booster administration demonstrated reliable diagnostic performance for biliary atresia. Notably, 43% of cases did not require booster administration, indicating that lesser radiation exposure may still yield comparable diagnostic accuracy.

Defensive fungal symbiosis on insect hindlegs.

Tympanal organs as "insect ears" have evolved repeatedly. Dinidorid stinkbugs were reported to possess a conspicuous tympanal organ on female's hindlegs. Here we report an unexpected discovery that the stinkbug's "tympanal organ" is actually a novel symbiotic organ. The stinkbug's "tympanum" is not membranous but a porous cuticle, where each pore connects to glandular secretory cells. In reproductive females, the hindleg organ is covered with fungal hyphae growing out of the pores. Upon oviposition, the females skillfully transfer the fungi from the organ to the eggs. The eggs are quickly covered with hyphae and physically protected against wasp parasitism. The fungi are mostly benign Cordycipitaceae entomopathogens and show considerable diversity among insect individuals and populations, indicating environmental acquisition of specific fungal associates. These results uncover a novel external fungal symbiosis in which host's elaborate morphological, physiological and behavioral specializations underpin the selective recruitment of benign entomopathogens for a defensive purpose.

Ultrasonography for the Detection of Osteomyelitis in Pediatric Patients With Soft Tissue Infection: A Pilot Study.

OBJECTIVES: To demonstrate the usefulness of ultrasonography for differentiating soft tissue infections with or without osteomyelitis in pediatric patients who underwent ultrasonography and subsequent magnetic resonance imaging (MRI). METHODS: Twenty-three patients were classified into 2 groups: 12 patients with and 11 patients without osteomyelitis based on MRI. Osteomyelitis using ultrasound is characterized by the presence of bone cortex irregularity and/or subperiosteal abscess formation. The diagnostic performance of ultrasonography for detecting osteomyelitis and subperiosteal abscess formation was compared with that of MRI. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were calculated with 95% confidence intervals (CIs). RESULTS: Of 12 osteomyelitis cases, 11 had abnormal bone marrow enhancement (one residual case did not undergo contrast enhancement study) and 5 had subperiosteal abscesses. The diagnostic accuracy of ultrasonography for osteomyelitis was 82.6% (number of correct diagnosis of osteomyelitis/total number = 19/23; 95% CI, 61.2-95.0) and for detecting periosteal abscess was 95.7% (number of correct diagnosis of periosteal abscess/total number = 22/23; 95% CI, 78.1-99.9), respectively. The sensitivity and specificity of ultrasonography for detecting osteomyelitis were 66.7% (95% CI, 34.9-90.1) and 100% (95% CI, 71.5-100), respectively. The sensitivity and specificity of ultrasonography for detecting periosteal abscess were 80% (95% CI, 28.4-99.5), and 100% (95% CI, 81.5-100), respectively. One-third of osteomyelitis cases could not be detected using ultrasonography. CONCLUSIONS: Ultrasonography may be useful for diagnosing osteomyelitis in pediatric patients; however, the technique appears limited by low sensitivity. However, it is more accurate for diagnosis of periosteal abscess in these patients.

Ultrasound for the evaluation of the urethra in pediatric patients.

Urethral lesions in pediatric patients can be visualized using ultrasonography. Therefore, sonographers and physicians should be familiar with the technique.

Clinical audit of ultrasonography for detecting sialoliths in the submandibular gland in paediatric patients: A comparison to computed tomography and magnetic resonance imaging.

Objectives: To compare the performance of ultrasonography with magnetic resonance imaging (MRI) and computed tomography (CT) for detecting submandibular sialoliths. Methods: Thirteen patients with suspected submandibular sialoliths who underwent ultrasonography and CT or MRI were included. Sialoliths were diagnosed using CT (11 cases) or MRI (two cases). The submandibular duct was classified into distal and proximal ducts based on the point around the mylohyoid muscle. Sialoliths located in the proximal duct were difficult to differentiate from those located within the submandibular gland (SMG). Therefore, the location of the sialoliths was classified as follows: within the SMG/proximal duct and within the distal duct. The ultrasound results were compared with CT/MRI results. Results: Of the 13 patients included, two had sialoliths in both the SMG/proximal duct and the distal duct, three had sialoliths in the SMG/proximal duct, and five had sialoliths in the distal duct on CT or MRI. In this small cohort, all five sialoliths in the SMG/proximal duct were detected by ultrasoonography; however, of the seven cases with sialoliths located in the distal duct, only three could be detected by ultrasonography. Conclusions: The incidence of sialoliths in the distal duct was higher than that in the SMG/proximal duct. Ultrasonography showed a good performance compared with CT/MRI in the SMG/proximal duct but not in the distal duct.

Point-of-care ultrasonography for the diagnosis and manual detorsion of testicular torsion.

Testicular torsion is a urological emergency caused by the loss of testicular tissue due to ischemic damage. Rapid diagnosis and urgent treatment play a crucial role in the management of testicular torsion. Manual detorsion can be performed at the bedside, thereby reducing the duration of ischemia. Recent studies have reported the use of point-of-care ultrasonography for diagnosing testicular torsion; however, no review article has focused on the ultrasonographic findings pertaining to manual detorsion. This review describes the diagnosis of testicular torsion and the ultrasonographic indications for manual detorsion. Spermatic cord twisting or the whirlpool sign, absence of or decreased blood flow within the affected testis, abnormal testicular axis, abnormal echogenicity, and enlargement of the affected testis and epididymis due to ischemia are the sonographic findings associated with testicular torsion. The following findings are considered indications for manual detorsion: direction of testicular torsion, i.e., inner or outer direction (ultrasonographic accuracy of 70%), and the degree of spermatic cord twist. The following sonographic findings are used to determine whether the treatment was successful: presence of the whirlpool sign and the degree and extent of perfusion of the affected testis. Misdiagnosis of the direction of manual detorsion, a high degree of spermatic cord twisting and insufficient detorsion, testicular compartment syndrome, and testicular necrosis were found to result in treatment failure. The success of manual detorsion is determined based on the symptoms and sonographic findings. Subsequent surgical exploration is recommended in all cases, regardless of the success of manual detorsion.

Ultrasonographic Findings of Catheter-Related Bloodstream Infection in Pediatric Patients.

BACKGROUND: Catheter removal is essential for treating catheter-related bloodstream infection (CRBSI); however, clinicians are sometimes hesitant to remove catheters in pediatric patients due to the difficulty of securing vascular access. Confirming the diagnosis of CRBSI is important to justify catheter removal. The purpose of this study was to describe the sonographic findings of CRBSI. MATERIALS AND METHODS: We included patients with a central venous catheter (CVC) or peripherally inserted central catheter (PICC) who had a positive blood culture and underwent ultrasound. The patients were classified as with or without CRBSI. Sonographic findings, such as the presence/absence of thrombus, venous wall thickening, hyperechogenicity, and fluid collection around the vein were compared using Fisher's exact test. RESULTS: Of the 58 patients, 38 (66%) were diagnosed with CRBSI. The presence of thrombus (19/38 vs 3/20, P = .011); and hyperechogenicity around the vein (14/38 vs 2/20, P = .035) differed significantly, but There was no significant difference in the presence of venous wall thickening (10/38 vs 1/20, P = .077), and fluid collection around the vein (5/38 vs 0/20, P = .153), did not differ significantly in patients with and without CRBSI, respectively. One-third of patients with CRBSI, including 11 (42.3%) patients with CVC, and 2 (16.7%) patients with PICC, did not have abnormal sonographic findings. CONCLUSION: Ultrasound findings are useful for diagnosing CRBSI. However, the sensitivity of sonographic findings is low and abnormal sonographic findings are sometimes absent in children with CRBSI; therefore, physicians should not rule out CRBSI based on normal sonographic findings, especially in patients a CVC and a positive blood culture.

Assessing the Usefulness of Ultrasonography for the Diagnosis and Evaluation of Intra-Orbital Lesions in Pediatric Patients: A Retrospective Analysis.

OBJECTIVES: To assess the usefulness of ultrasonography in the diagnosis and evaluation of extraocular intra-orbital lesions in pediatric patients. METHODS: Twenty-three pediatric patients with intra-orbital lesions who underwent both ultrasound and computed tomography/magnetic resonance imaging (CT/MRI) were included. The following parameters were evaluated using ultrasound: 1) lesion detection rate (presence or absence of lesions), 2) lesion characteristics, 3) lesion location (extraconal or intraconal), and 4) the lesion longest linear dimensions, and these were compared using Fisher's exact test and Mann-Whitney U test. RESULTS: Two lesions could not be detected using ultrasound; in the other 21 cases, the lesion characteristics diagnosed by ultrasound were correct. Diagnostic accuracy of detection and characteristics assessment using ultrasound were 91.3% and 91.3%, respectively. The lesion location was not significantly different between the two groups (intraconal/extraconal in those detected using ultrasound versus those in the absence on ultrasound = 7/14 versus 0/2, P > .999); however, in two cases that were not detected on ultrasound, the lesions were located at extraconal. Lesions that were small in longest linear dimensions on CT/MRI were not detected using ultrasound (the longest linear dimensions in lesions detected using ultrasound versus that in the absence of ultrasound: 29.5 ± 8.2 [range, 13-46] versus 10 and 11 mm, P = .043). CONCLUSIONS: Ultrasonography proved to be useful for visualizing and evaluating intra-orbital lesions except for lesions that were relatively small in size. Therefore, although ultrasound could not detect lesions located behind bone and bone invasion, it could be used for diagnosing and selecting treatment strategies for intra-orbital lesions.

Sonographic Findings of Cervical Chondrocutaneous Branchial Remnants-A Comparison With Dermal Lesions/Cysts and a Literature Review: A Pilot Study.

OBJECTIVES: Cervical chondrocutaneous branchial remnants (CCBRs) and dermal lesions, such as epidermoid cysts or brachial anomalies, including lateral cervical cysts/sinuses or dermal sinuses of anterior chest lesions, are usually located at the lower neck at the anterior or posterior border of the sternocleidomastoid muscle (SCM). We aimed to demonstrate the usefulness of ultrasonography in the differential diagnosis and evaluation of CCBRs. METHODS: We evaluated 22 lesions of 20 pediatric patients, classified into CCBR and dermal lesion groups. We used Fisher's exact test to evaluate differences between these groups in terms of lesion shape (low-echoic mass- or tubular-like), whether the lesion was adjacent to/in contact with the SCM or not, and the presence or absence of a concave SCM caused by the lesion. RESULTS: Of the 22 lesions, 8 were CCBRs, and 14 were dermal lesions. We found a significant difference in the presence/absence of adjacency to or contact with the SCM (presence/absence of adjacency to or contact with the SCM in CCBRs vs that in dermal lesions: 6/2 vs 1/13, P = .002) and presence/absence of lesion-induced concavity of the SCM (presence/absence of lesion-induced concavity of the SCM in CCBRs vs that in dermal lesions: 3/5 vs 0/14, P = .036). The lesion shape (low-echoic mass-like/tubular-like lesions) did not significantly differ between the two study groups (low-echoic mass-like/tubular-like lesions in CCBRs vs that in dermal lesions: 5/3 vs 11/6, P = .624). CONCLUSIONS: CCBRs have a strong association with the SCM. These sonographic findings may be useful in the differential diagnosis of dermal cervical lesions.

Complete Remission of Renal Scarring in Follow-Up DMSA Renal Scintigraphy After Urinary Tract Infection.

Our study aimed to investigate the association between the characteristics of patients/images and complete remission of renal scarring shown in the first chronic phase Technetium-99m dimercaptosuccinic acid (DMSA) renal scintigraphy images in children with urinary tract infection (UTI). Fifty children, who underwent the chronic phase of DMSA scintigraphy more than twice following UTI diagnosis and had renal scarring in the first chronic phase DMSA renal scintigraphy, were enrolled. They were classified into 2 groups: with and without complete remission of renal scarring on the second chronic phase DMSA renal scintigraphy. Renal scarring was classified into 3 grades based on severity per the image findings. Seven cases had complete remission from renal scarring. There were significant differences in age and severity. Renal scarring might be completely reversed in young children without severe findings on DMSA renal scintigraphy. Additional chronic phase examination may aid in follow-up completion and patients' peace of mind.

Point-of-Care Ultrasound for Mimicker Lesions of Incarcerated Inguinal Hernia.

Inguinal hernia is the most common surgical disease in pediatric patients, and urgent intervention such as manual reduction is needed for incarcerated inguinal hernia. Torsion of undescended testes, inguinal herniated ovarian torsion, and purulent lymphadenitis are mimickers of this condition. If these mimicker lesions are misdiagnosed as incarcerated inguinal hernia, manual reduction usually fails, and edematous and erythematous changes may occur in these mimicker lesions due to manual reduction. For physicians in the emergency department, prompt decisions and familiarity with the sonographic appearance of different contents within an inguinal hernia are important to accurately diagnose these mimickers. In this case series, we present sonographic images of a typical case of incarcerated inguinal hernia (an 11-month-old male with right incarcerated inguinal hernia) and three cases of mimicker lesions (a 7-month-old female with herniated ovarian torsion, a 7-year-old boy with undescended testicular torsion, and a 2-month-old male with purulent lymphadenitis). The incidence of incarcerated inguinal hernia is reported to be higher in males (80%), on the right side (60%), and in infants and toddlers. This information is important for diagnosing mimicker lesions. In addition, to prevent manual reduction in mimicker diseases, point-of-care ultrasound before manual reduction in suspected cases of incarcerated inguinal hernia is important.

Useful sonographic findings for diagnosing dermal metastases of rhabdomyosarcoma.

Rhabdomyosarcoma developing in deep locations, such as the genitourinary tract, and perianal and perineal regions, symptoms may be obscure. Dermal rhabdomyosarcoma metastases may be first symptom of that and those arise in the subcutaneous fat tissue, presenting as a high echoic area surrounded by a low echoic area, accompanied by a high echoic peripheral area. These sonographic findings might indicate an aggressive malignant disease, and that would be useful to differentiate from other dermal lesions.