INFANT COLIC

EPIDEMIOLOGY

Estimates of the prevalence of colic in infants range from 8 to 40 percent.^(1-3) The wide range is due to differences in diagnostic criteria, study design, populations, and family perceptions of "excessive and prolonged" crying.^(2,4)

The incidence of colic does not appear to differ among males and females, breast- and formula-fed infants, or full-term and preterm infants.^(5,6)

PATHOPHYSIOLOGY⁽⁷⁾:

Intestinal permeability to macromolecules is increased in some infants with colic; this reflects an immature function of the gastrointestinal tract and accounts for acquired food allergy.

Infantile colic is associated with elevated motilin levels. Motilin stimulates gastric and intestinal motility, and high motilin levels may lead to intestinal spasm. Exposure to cigarette smoke is associated with increased plasma and intestinal motilin levels.

There is also evidence for decreased contractility of the gallbladder in colicky infants. This hypocontractility may be due to a disturbance in cholecystokinin secretion.

NATURAL HISTORY:

Colic is commonly described as a behavioral syndrome characterized by excessive, paroxysmal crying. During episodes of colic, an otherwise healthy neonate or infant aged 2 weeks to 4 months is difficult to console. They stiffen, draw up their legs, and pass flatus.

Different feeding practices and crying may result in large amounts of air entering the gastric lumen, which suggests that excessive aerophagia may be associated with colic. Colonic fermentation is the second proposed source of excessive intestinal gas in infants. However, no experimental evidence supports either theory.

Colic improves spontaneously with time.^(5,8-11) Symptoms resolve in 60 percent of infants by three months of age and in 80 to 90 percent of infants by four months of age.^(5,9,10,11)

SIGN AND SYMPTOMS:

Following clinical features is used to distinguish colic from normal crying:⁽¹²⁾

• Paroxysms: The cry / fuss behavior of colic generally is paroxysmal.^(12,13) Colicky episodes typically have a clear beginning and end. The onset seems to be unrelated to what the infant was doing just before the "attack." The infant may have been happy, fussy, feeding, or even sleeping. These spells of crying occur suddenly, and often cluster during the evening hours.
• Qualitative differences: The cry of colic is qualitatively different from normal crying. It is louder, higher and more variable in pitch, and more turbulent and dysphonic than noncolicky crying.^(13-15) Colicky crying may sound as if the infant is in pain or is screaming rather than crying.⁽¹³⁾ The mothers of colicky infants describe their infant's cries as more urgent, piercing, grating, arousing, aversive, distressing, discomforting, and irritating than do the mothers of noncolicky infants.^(15,16,17)
• Hypertonia: Episodes of colic may be associated with physical characteristics associated with hypertonia.⁽¹³⁾ These include facial flushing, circumoral pallor, tense or distended abdomen, drawing up of the legs, clenching of the fingers, stiffening and tightening of the arms, or arching of the back.
• Difficulty consoling: Infants with colic can be difficult to console, no matter what the parents do. There may be periods when the crying diminishes, but the infant remains fussy.⁽¹³⁾ Relief may be noted after the passage of flatus or feces.

DIAGNOSTIC TESTS:

It can be helpful to schedule the evaluation of child during the time of day that the infant is fussy (if possible, given that colic often occurs in the evening).⁽¹⁸⁾ This allows the clinician to observe the crying behavior, the parents' soothing techniques, and the infant's ability to be soothed.

The evaluation typically includes a history and examination for identifiable causes of crying / fussiness. Laboratory or imaging studies generally are not necessary.

HISTORY: The history may provide clues to the etiology of infant's fussiness. It must assess identifiable causes of crying, as well as psychosocial factors that may be contributing to it.

Important aspects of the history in a child with colic include:^(19,20)

• The infant's feeding, stooling, urination, and sleeping patterns, including vomiting (helpful in evaluating the possibility of gastrointestinal, cardiovascular, and metabolic conditions)
• Prenatal and perinatal history, including risk factors for sepsis (e.g. premature rupture of membranes, maternal fever, maternal colonization with group B streptococcus)
• Psychosocial history, including assessment of parent-infant interactions, and the perceptions and interactions of extended family members (e.g. grandparents), which may play a role in parenting style and techniques for soothing
• Specific questions about the crying or fussiness, including:⁽⁵⁾
• When does the crying occur? Colicky crying typically occurs during the evening. Crying that occurs directly after feeding may be associated with air swallowing or gastroesophageal reflux, and may respond to changes in feeding technique (e.g. upright positioning, smaller volumes, etc.).
• How long does the crying last? Duration of crying may help to differentiate normal infant crying from colic.
• What do you do when the baby cries? The response to this question may provide information about soothing techniques that are helpful, not helpful, may exacerbate crying, or may be harmful (e.g., shaking).
• How and what do you feed the baby? Underfeeding, overfeeding, and inappropriate feeding are proposed etiologies of colic, and may respond to changes in feeding techniques.
• How do you feel when your baby cries? Responses may range from feeling inadequate as a parent, to feeling responsible for the crying, to fear of harming the infant if the crying continues.
• How has the colic affected your family? What is your theory of why the baby cries? Understanding what the family fears about the crying is helpful in formulating a management plan, particularly with respect to parental support.

EXAMINATION: Important aspects of the examination of the infant with colic include:⁽¹⁹⁾

• Observation of the infant and parent interaction during a bout of crying (provides information about the infant's ability to be soothed and the parents' soothing techniques; allows the clinician to see what the parents are going through)^(18,21)
• Assessment of temperament (e.g. sensitivity, irritability, soothability, intensity, adaptability^(21,22)) and responsiveness to stimuli (i.e. does the infant cry in response to touch or movement?)
• Plotting of growth parameters to look for deviations from the normal patterns (which generally preclude a diagnosis of colic)
• Assessment for identifiable causes of prolonged crying in infants, including:
• Assessment of hydration and subcutaneous fat (to evaluate adequacy of feeding)
• Assessment for tongue-tie, which may be associated with breastfeeding problems
• Eye examination for foreign body, corneal abrasion, infantile glaucoma (e.g. corneal enlargement or clouding), retinal hemorrhage (though fundoscopic examination may be difficult)
• Ear examination for otitis media
• Oropharyngeal examination for thrush
• Cardiovascular evaluation for signs of heart failure or supraventricular tachycardia (e.g. tachycardia, poor perfusion, S3 gallop, tachypnea)
• Evaluation of the abdomen for tenseness, tenderness, absence of bowel sounds (possible clues to an acute abdominal process such as intussusception, volvulus)
• Evaluation of perineum for diaper rash, testicular torsion, hair tourniquet, meatal ulcer, anal fissure, inguinal hernia
• Evaluation of the skin and musculoskeletal system for signs of trauma (including abusive trauma) or infection (e.g. hair tourniquet, bruising, decreased range of motion, pain with passive movement)
• Evaluation of the nervous system for abnormalities (e.g. bulging anterior fontanelle, asymmetry, increased or decreased tone)

A presumptive diagnosis of infantile colic can be made in an otherwise healthy infant <3 months of age who cries for no apparent reason for ≥3 hours per day on ≥3 days per week. Other causes of crying generally are excluded by the history and physical examination. The diagnosis of colic is confirmed in retrospect, after it has run its characteristic course.

DIFFERENTIAL DIAGNOSIS: Colic must be differentiated from other conditions that can cause prolonged crying or irritability in infants and may require specific treatment. This distinction can usually be made with history and examination. Colic has characteristic clinical features (paroxysms of crying that start and stop without obvious cause; normal growth, development, and examination). Other conditions must be considered in infants with poor weight gain, abnormal development, or abnormalities on physical examination. Virtually any illness/condition can present with crying; as examples:⁽²³⁾

• Tachycardia, tachypnea, pallor, poor perfusion may indicate heart failure
• Petechiae or bruising may indicate infection, trauma (including abusive trauma)
• Hypotonia may indicate neuromuscular disease, central nervous system disorder, or metabolic disease
• Full fontanelle may indicate meningitis or other condition associated with increased intracranial pressure
• Poor weight gain may indicate inadequate nutritional intake, absorption, or utilization; increased losses; or increased requirements
• Bilious or projectile vomiting may indicate gastrointestinal obstruction (e.g. pyloric stenosis, volvulus)
• Bloody stool may indicate cow's milk or soy-induced colitis, anal fissure, intussusception

TREATMENT OPTIONS:

FIRST-LINE INTERVENTIONS: As first-line interventions for colic, it is suggested to change the feeding technique and / or experimenting with a number of techniques to soothe the infant.^(22,24)

FEEDING TECHNIQUE: Feeding changes may be helpful for infants whose colic is associated with feeding problems (e.g. underfeeding, overfeeding, inadequate burping). Bottle-feeding the baby in a vertical position (using a curved bottle) in combination with frequent burping may reduce swallowed air. Using a bottle with a collapsible bag also may help reduce air-swallowing.⁽²⁵⁾

SOOTHING TECHNIQUES: It is suggested that parents experiment with one or more of the following techniques for soothing the infant and / or decreasing sensory stimulation. Parents can be instructed to try a technique for several minutes and if it doesn't work, move on another soothing technique; the success or failure of individual soothing techniques may vary from one episode of colic to the next.

• Using a pacifier
• Taking the infant for a ride in the car or a walk in thestroller / buggy
• Holding the infant or placing them in a front carrier⁽²⁶⁾
• Rocking the infant
• Changing the scenery (or minimizing visual stimuli)
• Placing the child in an infant swing
• Providing a warm bath
• Rubbing the infant's abdomen
• Hip healthy swaddling(i.e. with room for hip flexion, knee flexion, and free movement of the legs^(27-29)
• Playing an audiotape of heartbeats
• Providing "white noise" (e.g. vacuum cleaner, clothes drier, dishwasher, commercial white noise generator, etc.); commercial white noise generators (sometimes called infant sleep machines)

UNPROVEN INTERVENTIONS: A number of other interventions for infantile colic have been evaluated in randomized trials with methodologic weaknesses or inconsistent results. Given these limitations, generally, these interventions are not suggested for infantile colic. However, they may be suggested for some patients on a case-by-case basis after a discussion of the potential risks and benefits if first-line interventions have been unsuccessful after several days to weeks.

DIETARY CHANGES: Dietary changes vary depending upon whether the infant is formula-fed or breastfed.

Formula-fed infants

• Extensive hydrolysate formula: A one-week trial of an extensive hydrolysate infant formula is an option for formula-fed infants with colic that has not responded to first line-interventions. A subgroup of infants with colic may have an allergy or intolerance to cow's milk formula, although infants with allergy or intolerance usually have associated clinical features (e.g. bloody stool, vomiting, rash, etc.).

Hydrolysate formula may be continued if there is a decrease in crying/fussiness. The response usually occurs within 48 hours.⁽³⁰⁾ The original formula is resumed if there is no change in the infant's symptoms (hydrolysate formulas are more expensive than cow's-milk-based formulas).

• Soy protein formula: It is not suggested to change from cow's milk to soy protein formula for formula-fed infants with colic. The benefits of soy versus cow's milk protein in the prevention and management of colic are unproven.⁽³¹⁾ Studies comparing the effects of soy and hypoallergenic formulas on the reduction of colicky symptoms are lacking.

Neither the American Academy of Pediatrics Committee on Nutrition nor the National Institute for Health and Care Excellence recommend soy protein formula for the treatment of infantile colic.^(31,32)

• Fiber-enriched formula: Fiber-enriched formulas is not recommended for formula-fed infants with colic. In a randomized crossover trial in 27 term infants in which the investigators were blinded but the parents were not, fiber supplementation of soy-protein formula did not affect the average daily duration of crying.⁽³³⁾ However, the parents of 18 infants found the fiber-supplemented formula beneficial in alleviating colic symptoms.

BREASTFED INFANTS: A time-limited trial of a decrease in maternal milk product consumption or a hypoallergenic maternal diet (e.g. no milk, eggs, nuts, wheat) is an option for breastfed infants with colic that has not responded to first-line interventions and whose parents have difficulty coping. A subgroup of infants with colic may have food allergy or allergy to cow's milk, although infants with allergy usually have associated clinical features (e.g. rash, wheezing). Maternal dietary changes may be particularly beneficial if the mother is atopic or the baby has symptoms of cow's-milk allergy (e.g. eczema, wheezing, diarrhea, or vomiting).⁽³⁴⁾

PROBIOTICS: Probiotics are not suggested for the routine management of colic in breastfed or formula-fed infants. The evidence of benefit is insufficient. Although probiotics are better studied than other interventions for colic, and there is some evidence that particular strains may be associated with decreased crying time in some infants, additional trials are necessary before probiotics can be routinely recommended.

LACTOBACILLUS REUTERI: Meta-analyses (35) of six heterogeneous randomized trials^(36-41) suggesting that Lactobacillus reuteri decreases crying time, particularly in breastfed infants.

LACTASE: Lactase is not suggested for the treatment of infantile colic. The benefits of lactase remain unproven. Randomized trials of lactase treatment for infantile colic have conflicting results.^(42-46)

The National Institute for Health and Care Excellence Clinical Knowledge Summary for infantile colic suggests a one-week trial of lactase as an option for infants of parents who feel unable to cope despite advice and reassurance.⁽³²⁾

SUCROSE: Sucrose is not suggested for the treatment of colic. Although oral sucrose appears to reduce some types of pain in neonates, the evidence that it is beneficial in reducing crying in colicky infants is limited.^(42,47) In a randomized crossover trial in 19 infants, 12 improved subjectively with sucrose.⁽⁴⁸⁾ However, the effect was short-lived (30 minutes to 1 hour maximum).

INFANT MASSAGE: Infant massage for the treatment of infantile colic. A 2010 systematic review found no evidence of benefit and the potential harm of unsettling or over-stimulating colicky infants.⁽⁴⁹⁾

SIMETHICONE: Simethicone is not suggested for the treatment of infantile colic. Simethicone is a medication that causes gas bubbles to coalesce, facilitating expulsion.⁽⁵⁰⁾ Simethicone is generally considered to be safe, but it may interact with levothyroxine in infants being treated for congenital hypothyroidism resulting in hypothyroidism.⁽⁵¹⁾

HERBAL REMEDIES: Herbal remedies (e.g. herbal teas, fennel seed, Gripe water [a mixture of herbs and water]) is not suggested for the treatment of infantile colic. Although a few randomized trials suggest that specific herbal remedies may be beneficial in reducing crying compared with placebo.^(52-54), the benefits are largely unproven.⁽⁴⁷⁾

HOMEOPATHIC REMEDIES: Homeopathic remedies is not suggested for the treatment of colic. They have not been proven to be effective.

Homeopathic remedies often are considered nontoxic because of the low concentrations of active ingredients. However, the labels of homeopathic products may not report all of the ingredients, some of which may have toxic effects.⁽⁵⁵⁾

DICYCLOMINE HYDROCHLORIDE: is an anticholinergic drug that has been proven in clinical trials to be effective in the treatment of colic. However, because of serious, although rare, adverse effects (e.g. apnea, breathing difficulty, seizures, syncope), its use cannot be recommended.⁽⁵⁶⁾

GOAL OF THERAPY:

The goal of the therapy is to decrease crying and bolster the infant-family relationship. The goals of management are to help the parents cope with the child's symptoms and to prevent long-term sequelae in the parent-child relationship

GUIDELINES:

To view, “American Family Physician guidelines on Infantile Colic”, please click on below link:

http://www.aafp.org/afp/2004/0815/p735.html

CONSULTATION AND COUNSELING:

Parental support is the mainstay of the management of colic. It may influence the way the parents view their ability to care for their child.

Important aspects of parental counseling include:^{(18,22,32,50,57-60)}

• Education that colic is common and usually resolves spontaneously by three to four months of age
• Reassurance that the infant is not sick; this may require frequent follow-up (either by phone or in person)
• Education that colic it is not caused by something they are doing or not doing; it does not mean that the infant is rejecting them
• Acknowledging that the infant is difficult to soothe and that you know that they are doing the best they can; this is essential in preventing the parents from feeling as if they have failed
• Providing tips for techniques to soothe the baby
• Encouraging the parents to take breaks from the crying infant (e.g. taking turns with the infant during the colicky period, asking a relative or friend to babysit so they can have a break, placing the crying infant in his or her crib).
• Acknowledging that feelings of frustration, anger, exhaustion, guilt, and helplessness are normal

FOLLOW UP:

The frequency of follow-up for colicky infants is individualized. Some infants and families may require frequent follow-up (by phone or in person) and reexamination to be reassured that the infant is continuing to do well and growing normally.⁽⁵⁾ Other infants, whose parents are coping well and have strong support networks can be seen less frequently (e.g. at regularly scheduled health maintenance visits). In all cases, parents should be counseled to return if the infant develops symptoms that were not present during the initial evaluation (e.g. vomiting, rash).

PRECAUTIONS:

Colic cannot be prevented, but if distress is related to feeding, then frequency of episodes will be lessen by trying following preventions. Parents should be guided on below mentioned preventions.

• Hold baby upright when feeding to prevent themswallowing air; wind them often, and especially after a feed.
• After feeding your baby, be sure to burp them over your shoulder or on your knee until they release some gas.
• Feed smaller amounts more frequently.
• Ifbreast-feeding avoid too much caffeine in your
• Try to soothe baby with movement such as vibration (for example by taking a trip out in the car) or with white noise, for example by placing your baby in a seat near a washing machine or vacuum cleaner.
• Avoid over-stimulating a baby
• Hold your child during a crying episode if this helps.
• Give baby a warm relaxing bath or try to create a peaceful soothing environment.
• Try giving your baby a gently tummy massage.

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