OBJECTIVE: Intussusception is the most common cause of acute intestinal obstruction in infants and young children. Diagnosis of the condition could be tricky, sometimes causing diagnostic confusion with other conditions. The classic triad of abdominal pain, vomiting and bloody stool are easy to recall but may delay diagnosis in patients lacking them. Over the past decades, several authors have reported on atypical presentations of intussusception with neurological signs and symptoms. Lethargy is reported most frequently.
CASE: A previously well and active, 17-month-old baby boy presented with sudden pallor and lethargy since 12 hours before admission, followed by loose stools mixed with blood and mucus and vomiting. There was no colicky abdominal pain as he didn’t cry or drew up the lower limbs to the abdomen as if to reduce pain. There were no history of fever, cough, any urinary problems, diarrhea or constipation, trauma nor convulsions. His feeding history was unremarkable. On physical examination, he was lethargic, responsive only to pain stimuli without signs of shock. His bowel sound was increased and a palpable mass was found in the epigastrium of non-distended abdomen. After nasogastric placement, greenish-colored residues were obtained. Abdominal ultrasound showed the target sign, a hallmark of the intussusception. Signs of bowel obstruction was shown as well on abdominal X-ray examination. Patient underwent exploratory laparotomy and found ileocolocolic intussusception, milking procedure was performed to the viable bowel. The patient was recovering well.
CONCLUSION:  The presence of lethargy in children in addition to the presence of any one or two symptoms of the classical triad should alert the clinician to these subtle features of intussusception. An early recognition of intussusception may improve the global prognosis as the duration of the intussusception is related to the pathological changes in the bowel and the outcome of treatment.