The current study included 120 patients; their age ranged between five days and 18 years old. There was slight male predominance (64 patients) in comparison to 56 female patients with a male: female ratio of 1.14:1.
The distribution of the studied patients according to their age group was shown in table 1. Most of the studied patients were above 10 years with the least frequency below one-year-old. There were no patients between five and ten years old.
All of the studied patients presented with abdominal pain. Different presentations were found among our studied patients with different frequencies as seen in table 2.
Appendicitis being the most frequent cause of acute surgical abdomen in the pediatric age group was the most common presentation in our study (40 patients, 33.3%) followed by intussusception (16 patients, 13.3%) with different frequencies among different pathologies as shown in figure 1.
As the most common diagnosis was acute appendicitis; most of the studied patients presented with right iliac fossa pain (n=24, 20%). There were only four patients who presented with epigastric pain (3%). The remaining patients presented with variable sites of abdominal pain with different frequencies as seen in figure 2
There were 40 patients having appendicitis in our study, it was correctly diagnosed by US in 36 patients and the remaining four patients who were not initially diagnosed by ultrasound were proved later on by CT as having appendicitis.
The age of 28 patients was above ten years old; 24 males and four females, while the remaining 12 patients were females below the age of five years. Clinically, 80% of children had at least two of the following presentations: right iliac fossa pain, fever, nausea/vomiting, diarrhea, and rebound tenderness.
The US findings included appendicular distension with the outer diameter of the appendix measuring more than 6 mm in 32 patients, echogenic peri-appendicular fat along with fluid collection and abnormal vascularity in 36 patients, mesenteric edema in 24 patients, bowel dilatation and mesenteric lymph node enlargement in 20 patients and finally wall thickening in all patients. (Figure 3)
Four male patients aged over ten years were diagnosed by US as having appendicular mass. All of them complained of severe abdominal pain, with signs of peritonitis and generalized sepsis.
The US scan revealed dilated appendix more than six mm in its outer diameter, wall thickening, echogenic peri-appendicular fat, fluid collection, wall thickening, mesenteric edema, and lymph node enlargement, forming a mass-like structure measuring 6.4x3.9 cm. CT findings included appendicular dilatation more than six mm in diameter, along with wall thickening, mucosal enhancement, perforation, a peri-appendicular fluid collection as well as fat stranding.
There were 16 male patients diagnosed as having intussusception in our study and all of them were under the age of two years. Clinically, they presented with varying combinations of vomiting, abdominal pain, red currant jelly stool, and excessive crying. US scans of all patients showed mesenteric edema; along with concentric alternating echogenic and hypoechoic layers representing the target sign; this was associated with enlarged mesenteric lymph nodes. (Figure 4)
Eight male patients in our study were diagnosed as having acute acalcular cholecystitis by US; all of them were over 10 years old. Patients with this pathology complained of right upper quadrant abdominal pain, vomiting, and fever. The US findings showed gall bladder wall thickening of more than 3 mm, peri-cholecystic fluid collection, and abnormal vascularity denoting an inflammatory process
Eight female patients aged below 12 months old were diagnosed by US as having midgut volvulus. Clinically; those patients complained of a distended and tender abdomen, excessive crying, and bilious vomiting. The US scan in midgut volvulus revealed a clockwise whirlpool sign on color Doppler US in which the superior mesenteric vein (SMV) was seen swirling with the small bowel loops around centrally placed superior mesenteric artery (SMA) in all patients. This was associated with bowel dilatation, wall thickening in four patients, fluid collection, and abnormal vascularity in all patients.
Eight patients over the age of 10 years had renal stones in our study; four males and four females. Clinically, those patients complained of loin pain. Half of those patients have been diagnosed by US initially and the other half were diagnosed later on by CT.
Twelve patients had been diagnosed as having ureteric stones, eight males and four females; all of them were over the age of ten years. Four patients were diagnosed by US while the other eight patients were diagnosed by CT scans. The main complaint of all the patients was severe abdominal pain. The US scans of all of the patients revealed urinary system dilatation while only four patients had a urinary tract stone which was seen as echogenic foci with posterior acoustic shadowing.
There were four female patients over 10 years old who presented with left lion pain after ingestion of a large amount of oral fluids. The US examination of such patients revealed left hydronephrosis with dilatation of the left renal pelvis more than 16 mm and collapsed. There were no associated urinary stones in those patients.
Four patients were diagnosed by US as having endometrioma; all of those females were over 10 years old. Clinically, they complained of lower abdominal and pelvic pain.
Eight female patients over ten years old were diagnosed by US as having hemorrhagic cysts and complaining of severe pelvic pain. Concerning hemorrhagic cyst, the US scan of those patients revealed a cystic ovarian mass with mixed cystic and solid pattern measuring over 4 cm in diameter and exhibiting posterior acoustic enhancement, while only one patient had a pelvic fluid collection.
Eight female patients over ten years old were diagnosed by US as having ovarian torsion. Clinically, the patients complained of severe non-specific lower abdominal and pelvic pain sustained nausea and vomiting. The US scan of those patients showed an enlarged adnexal lesion with peripheral cysts confirming the mass to be ovarian in origin, a small amount of free pelvic fluid collection was also noted. Color Doppler US showed a complete absence of blood flow in the ovary.
The overall sensitivity of US in our study was about 88.5%, with variable percentage among different pathologies as seen in figure 5. Also, the overall specificity of US in the diagnosis of different pathologies in our study was about 88.2% with different percentages among different diseases as seen in figure 6