What toxic substance found in common houseplants (such as this one pictured) causes intense irritation of skin and mucous membranes?
[Left image from Dr. Bryant Allen, MD, and right image from AJ West -Wikimedia Commons]
Which of the following chronic exposures could produce lesions such as this on the hands, feet, and trunk?
[Image from Wikimedia Commons]
What is this pictured spider that can inflict a deadly bite?
[Image from thebeachcomber, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia]
A 6-year-old female with a past medical history of immune thrombocytopenia presents to the Emergency Department (ED) for concerns of dysarthria that started the day prior to arrival. The patient’s mother denies any recent trauma, including head injury.
Her physical exam is remarkable for a mild right-sided facial droop with forehead sparing and dysarthria.
The patient’s ED workup shows the following:
Although rare, pediatric intracranial hemorrhage (ICH) contributes to almost half of all childhood strokes and can cause lifelong disability and death [1]. One 3-center prospective study on pediatric ICH noted a 9% mortality rate with ⅓ of survivors having “significant disability” at 2-year follow-up [2]. Primary predictors of adverse outcomes from pediatric ICH involve the following [2-4]:
Multiple studies consistently point to vascular causes such as arteriovenous malformation as a leading risk factor for spontaneous pediatric ICH followed by hematological pathologies including coagulation deficiencies [5-7]. No matter the cause, the sequelae of pediatric ICH can be devastating making early detection and immediate intervention essential for better outcomes. Unfortunately, given children often present with vague and non-specific symptoms, there is often a delay in presentation to care and in diagnosis [8]. Unfortunately, in contrast to adults, there are no set guidelines for the management of pediatric ICH despite its associated morbidity and mortality.
Although headache is the most common presenting symptom, other symptoms can vary [6,8,9]. In one study, children <6 years old were more likely to present with symptoms such as seizures and altered mental status, while children ≥6 years presented more with focal deficits, headache, vomiting, and altered mental status [9].
| Presenting Symptom/Finding | Incidence |
|---|---|
| Headache | 46-80% |
| Vomiting | 21-64% |
| Altered mental status | 37-50% |
| Seizures | 37-54% |
| Focal deficits (hemiparesis and aphasia) | 16-50% |
Given how rare pediatric ICH is, consider other diagnoses when a patient presents with focal deficits, altered mental status, and/or vague symptoms such as headache and weakness.
Emergency medicine physicians should have strong suspicion for ICH particularly in the setting of a pediatric patient presenting with acute onset of headache, vomiting, altered mental status, seizure, and/or focal deficits.
If a patient has a confirmed ICH, consultation with neurosurgery is required. Immediate transfer may be necessary if your facility does not have neurosurgical services. Further management includes:
The patient was transferred to a tertiary care center. Further imaging confirmed an intraparenchymal hemorrhage in the left frontal lobe and right parietal lobe with midline shift. No underlying lesions or vascular malformation were seen.
Management: The patient was admitted to intensive care and received tranexamic acid and a platelet transfusion. She was monitored by neurosurgery but no surgical interventions were needed. For her idiopathic thrombocytopenia, she received steroids and IV immunoglobulin.
Hospital Course: Her deficits and platelet count improved during her stay, and she was discharged on hospital day 5 with outpatient neurology and hematology follow-up.
Outpatient: Repeat imaging 3 weeks after discharge showed resolution of the midline shift and decrease in hemorrhage size.
Read more pediatric EM blog posts in the PEM Pearls series.
What caustic exposure from the pictured item can lead to ocular injury?
[Image from Istockphoto]
Which type of foreign body should be suspected in a child who is drooling and has the following x-ray?
Read this tutorial on the use of point of care ultrasonography (POCUS) for pediatric soft tissue ultrasonography. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.
Wendy is a 7-year-old girl who comes into the emergency department with redness, swelling, and pain on her left calf. Her symptoms started 1 week ago as a scratch which progressively got more red and painful. There has been no drainage from the lesion. She has had no fevers, but endorses elevated temperatures of 99 F.
On arrival, her vital signs are:
| Vital Sign | Finding |
|---|---|
| Temperature | 100.1 F |
| Heart Rate | 95 bpm |
| Blood Pressure | 105/68 |
| Respiratory Rate | 20 |
| Oxygen Saturation (room air) | 100% |
Figure 1. Linear ultrasound transducer
Figure 2. Left: Water bath technique; Right: Ultrasound of a toe using a water bath (image courtesy of The Pocus Atlas and Moudi Hubeishy, MD)
Figure 3. Normal soft tissue layers on ultrasound (image courtesy of The Pocus Atlas)
Normally on a soft tissue ultrasound, you will see layers of defined structures separated by fascial planes.
Cellulitis has a spectrum of appearances on ultrasound. Early cellulitis may present as skin thickening (Figure 4).
Figure 4. Cellulitis with skin thickening
As cellulitis progresses, there is effacement of the clearly differentiated structures seen above, and the tissue layers may appear hazy and hyperechoic. More advanced cellulitis may have “cobblestoning” which is the result of edematous fluid separating fat globules in the subcutaneous tissue.
Figure 5. Cellulitis with cobblestoning
Abscesses can have varied appearances. They can be anechoic (black) or filled with debris leading to a heterogeneous appearance of contents. The rim may be echogenic or blend in with surrounding tissue. They may be well-circumscribed or may have irregular borders.
 A. Abscess with irregular borders and heterogeneous appearance |  B. Well-circumscribed abscess with heterogeneous debris |  C. Larger abscess with well-circumscribed borders |
 D. Abscess with irregular borders and surrounding cellulitis |  E. Abscess with irregular borders and more homogenous appearance |  F. Superficial abscess with well-circumscribed borders |
Placing color Doppler flow on a suspected abscess is helpful to differentiate it from a lymph node or blood vessel (see “Abscess Mimickers” section for lymph node examples). It may also aid in identifying nearby vasculature.
Figure 6. Abscess with color Doppler flow
Abscesses may exhibit posterior acoustic enhancement, which results in an enhanced transmission of ultrasound waves through a fluid-filled structure. Sometimes the abscess may not be as obvious and appear less anechoic due to debris. A squish (or swirl) sign may be elicited by putting pressure on the region, which will cause movement of the abscess contents. This finding has also been called “pus-talsis”.
Figure 7. Abscess with posterior acoustic enhancement
Abscesses should be measured in 2 planes. Measure depth in 1 plane and length in 2. An easy way to remember this is to measure a plus sign (+) in one view, and a minus sign (-) in the other.
Figure 8. Measurement of abscess in two planes (images courtesy of Dr. Munaza Rizvi)
Lymph nodes appear as ovid and well-circumscribed structures on ultrasound and may be confused for abscesses. They may be differentiated by their homogenous echotexture, central echogenic hilum. When inflamed, they may exhibit internal vascularity which should not be seen in an abscess.
Figure 9. A lymph node with a hilum (left) and a reactive inguinal lymph node with central vascularity (right)
Cysts are fluid-filled, well-circumscribed structures which may be similar to abscesses. A common soft tissue cyst is an epidermoid cyst, which is a subepidermoid nodule filled with keratin. In addition to physical exam clues which may help distinguish cysts from abscess, cysts are typically very well-circumscribed and more homogenous in appearance.
Figure 10. Epidermoid cyst (image courtesy of The Pocus Atlas and Dr. Robert Jones)
Soft tissue foreign bodies are a common pediatric presentation and can be easily identified on ultrasound. X-rays can be used to identify foreign bodies; however, their use is limited to radiopaque objects. On ultrasound, foreign bodies often appear as a hyperechoic defect.
Figure 11. Hyperechoic foreign body (glass) embedded in the soft tissue of a foot with posterior shadowing
Foreign bodies embedded for a prolonged time may have signs of infection, such as cellulitis or abscess (Figure 12).
Figure 12. Wooden splinter embedded in a patient’s plantar foot with surrounding fluid collection consistent with abscess
A foreign body’s composition can affect how it appears on ultrasound. Different materials can produce characteristic ultrasound artifacts.
| Foreign Body | Ultrasound Findings | Ultrasound Image |
|---|---|---|
| Wood | Hyperechoic with posterior shadowing |  |
| Glass | Hyperechoic with posterior shadowing May have comet tail artifact |   Images courtesy of Dr. Ashkon Shaahinfar |
| Metal | Very hyperechoic Often has a comet tail or reverberation artifact |  Image courtesy of The Pocus Atlas and Robert Jones DO, FACEP |
Ultrasound assistance in foreign body removal may be static (used to locate the foreign body’s position) or dynamic (using ultrasound to guide foreign body removal in real-time). Measuring the foreign body and assessing the object’s depth on ultrasound may assist in determining if bedside removal versus surgical removal is indicated.
Limited evidence suggests that there may be some sonographic differences between the papular urticaria of a “skeeter syndrome” and local cellulitis. On ultrasound, both findings will have thickening of dermal and subcutaneous tissues. Angioedema characteristically includes more linear, horizontal, striated bands — in comparison to cobblestoning found in cellulitis [1]. However, additional studies are needed to confirm this.
Figure 13. Ultrasound of angioedema (left) and cellulitis with cobblestoning (right). Angioedema image courtesy of Dr. Laura Malia.
Necrotizing fasciitis is a rare pediatric diagnosis but a rapidly progressive and life-threatening condition if not identified quickly. While necrotizing fasciitis is primarily a clinical diagnosis, imaging may be helpful when the diagnosis is uncertain. Computed tomography (CT) and magnetic resonance imaging (MRI) have good test characteristics; however, these tests are time-consuming and may not be available in all centers. CT also involves ionizing radiation. Point-of-care ultrasound has the benefit of rapid bedside use and lack of ionizing radiation.
On ultrasound, early necrotizing fasciitis presents with thickening of the subcutaneous tissue, similar to cellulitis. Fluid in the fascial layers may also be present, and a thick layer of pre-fascial fluid >4 mm has been associated with necrotizing fasciitis [2]. Subcutaneous air with dirty shadowing (Figure 14) is a characteristic but late finding in necrotizing fasciitis. These findings may be recalled using the “STAFF” mnemonic [3]:
Note: It may be difficult to distinguish early cases of necrotizing fasciitis from cellulitis. Therefore ultrasound should not be used to exclude necrotizing fasciitis. Patients with findings concerning for necrotizing fasciitis require additional work-up and surgical consultation.
Figure 14. Necrotizing fasciitis on POCUS exam showing the presence of air with dirty shadowing within soft tissue (image courtesy of Dr. Di Coneybeare)
For additional reading on ultrasounding necrotizing fasciitis, see these ALiEM articles:
There have been multiple studies (Table 3) that support the use of soft tissue POCUS for identification of cellulitis or abscess. Soft tissue POCUS has been shown to have good sensitivity and specificity. It has also been shown to be superior to clinical assessment in several pediatric studies.
POCUS can also reduce the length of stay (LOS) for our patients. In one pediatric study including 3,094 children suspected of a soft tissue infection who underwent either POCUS or radiology department ultrasound, POCUS was shown to have a shorter median LOS by 73 minutes (95% CI 52.4-93.6 min) [4].
| Study | N | Methods | POCUS Sensitivity (95% CI) | POCUS Specificity (95% CI) | Conclusions |
|---|---|---|---|---|---|
| Gottleib et al., Ann Emerg Med 2020 [5] | 2,656 | Systematic review of adult and pediatric studies | 94.6% (89.4-97.4%) | 85.4% (78.9-90.2%) | POCUS has good diagnostic accuracy. Led to correct change in management in 10% of cases. |
| Lam et al., J Emerg Med 2018 [6] | 327 | Prospective cohort study of children 6mo-18yrs comparing clinical assessment to POCUS | 90.3% (83.4-94.7%) | 80% (70.0-87.4%) | POCUS changed management in 22.9% of cases* |
| Subramaniam et al., Acad Emerg Med 2016 [7] | 800 | Systematic review of adult and pediatric (patients from birth – 21yrs) studies | 97% (94-98%) | 83% (75-88%) | POCUS may assist physicians in distinguishing cellulitis versus abscess. |
| Adams et al., J Pediatr 2015 [8] | 151 | Prospective cohort study of patients 3mo-21yrs comparing clinical assessment to POCUS | 96% (90-99%) | 87% (74-95%) | POCUS changed management in 27% of cases.** For every 4 ultrasounds performed, 1 correct change in management. |
| Sivitz et al., J Emerg Med 2009 [9] | 50 | Prospective cohort study of children <18yrs comparing clinical assessment to POCUS | 90% (77-100%) | 83% (70-97%) | POCUS changed management in 22% of cases. |
After reviewing the literature, you decide to perform a POCUS to evaluate for skin abscess. You place a linear, high-frequency transducer over the patient’s affected area and you observe the following:
The patient underwent successful incision and drainage of the abscess, and she was discharged home with antibiotics.