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Irritability and intractable crying may be the presenting complaint for a wide range of medical problems in infants and children, some of which are potentially serious. Recently it has been estimated that 5% of infants presenting to the emergency department with crying have a serious underlying illness and two-thirds of these cases may be identified through careful history and physical examination.1 Symptoms may also begin after hospitalization. Hospital providers must be able to differentiate significant irritability and intractable crying from developmentally appropriate crying. They must be familiar with the common causes of irritability and intractable crying as well as the more unusual causes and a stepwise approach to evaluation.
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Irritability is a state of increased sensitivity to stimuli; it may also be described by parents as fussiness, whining, or increased crying. Crying is the primary way that infants and young children express hunger, thirst, fear, fatigue, desire for attention, and discomfort or pain. When caregivers have taken the usual measures to address these common needs, such as feeding and holding the child and changing the diaper, yet the child continues to cry, the child is said to be inconsolable or to have intractable crying.
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The quantity as well as the quality of crying behavior should be considered. What qualifies as excessive crying varies based on the age and developmental level of the child, as well as the clinical scenario. Normal infants cry most during the first 3 months of life; during this period, serious illness may present with few or only subtle signs and symptoms, making evaluation in this age group particularly challenging.
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Crying should also be evaluated to determine whether it is appropriate for the clinical scenario. For example, a febrile infant with a viral upper respiratory infection is likely to be irritable and may cry more than usual. However, crying with movement of the child’s lower extremities should lead to suspicion of an alternative cause, such as meningitis or a septic hip joint. Stranger anxiety—which appears at around 8 to 9 months of age, peaks at 12 to 15 months, and decreases thereafter—may manifest as inconsolable crying during examination; however, an otherwise healthy child should be comforted and calmed in the arms of a caregiver.
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A change in the character of a child’s cry may also be significant: louder, higher pitch, or more urgent tone or a weak, stridulous, or hoarse cry may suggest the presence of illness.
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Irritability may result from pain, discomfort, or fatigue, direct neurologic insult, or altered metabolic or endocrine status. Crying in infants and young children is an involuntary action that serves physiologic and protective purposes. A newborn’s first cries enable essential changes in the cardiorespiratory system during the transition to postnatal life. Crying increases to almost 3 hours per day, on average, by 6 weeks of life and decreases thereafter. During this ...