Introduction

Floating-Harbor syndrome (FHS) is a rare genetic disorder characterised by distinct facial features, short stature, delayed speech development, and various other developmental delays. The syndrome is named after the two hospitals—Floating Hospital in Boston and Harbor General Hospital in California—where the first cases were described. The condition is caused by mutations in the SRCAP gene, which plays a role in chromatin remodelling and gene expression.¹ Although the syndrome is relatively uncommon, it presents significant challenges, particularly in feeding and nutrition, which are critical for the overall development and well-being of affected individuals.

Understanding Floating-Harbor syndrome

Floating-Harbor Syndrome manifests with a set of clinical features that are often noticeable from early childhood. The most prominent characteristics include a triangular face, a wide mouth with a thin upper lip, and deep-set eyes. These facial features, and delayed bone age, contribute to the short stature observed in most individuals with FHS. Additionally, children with FHS often experience significant delays in speech and language development, which can further complicate their ability to communicate their needs, including those related to feeding.¹

In FHS, growth patterns are atypical, with many children experiencing growth retardation from infancy. Short stature is a key sign, with most individuals born underweight and having a normal head circumference. Early weight gain and linear growth are poor, and bone age is significantly delayed but typically normalises by ages six to 12. The average adult height is 140-155 cm.¹ Managing their nutritional needs is challenging due to the interaction of physical, cognitive, and developmental factors.

Feeding challenges in FHS

Feeding challenges are among the most significant issues experienced by individuals with Floating-Harbor Syndrome. These challenges often begin in infancy and can persist into adulthood, necessitating ongoing management and intervention.

Oral motor dysfunction

Oral motor dysfunction is a significant feeding challenge in individuals with FHS. This condition impairs the muscles while chewing and swallowing, making it difficult for affected individuals to manage food intake properly. Infants with FHS may have trouble with breastfeeding or bottle feeding due to insufficient suckling reflexes, which can lead to poor nutritional intake and slow weight gain. As these children grow, they may encounter further difficulties while chewing and swallowing solid foods, resulting in a restricted diet and exacerbated nutritional deficiencies.¹

In a case involving a 7-year-old Romanian boy with FHS, severe expressive language delays were observed. He could only use simple sentences, reflecting how oral motor dysfunction impacts feeding and speech.³ Similarly, a 2.5-year-old Turkish boy with FHS had noticeable speech impairment and dysmorphic oral features, including small, abnormally shaped teeth with cavities, which suggests significant oral motor challenges.⁴ Another case describes a 5-year-old boy who initially struggled with pronunciation but showed improvement with therapy, highlighting the impact of oral motor dysfunction on speech development.⁵

Oral motor dysfunction affects feeding and speech production, as the muscles used for eating are crucial for articulation. Addressing these issues is vital for enhancing both feeding abilities and speech development. For example, a patient with FHS had minimal speech at age 2.5 years, demonstrating significant articulation difficulties and only beginning to use simple phrases.⁶ In a separate report, a 13-month-old girl spoke only single words and by age 4 had severe delays in expressive speech, characterised by a high-pitched, nasal voice. By age 8, she continued to experience dyslalia and impaired comprehension, underscoring ongoing oral motor challenges.⁷ Another patient also showed delayed speech development with only a few words spoken at age 2, though detailed descriptions of oral motor dysfunction were not provided.⁷

Gastrointestinal issues

Gastrointestinal (GI) problems are common in individuals with FHS and can significantly impact feeding and nutrition. Reflux, constipation, and other GI disorders are reported in three cases,^4,5,6 complicating the already challenging process of maintaining adequate nutrition. In the first case, the boy experienced feeding difficulties, gastroesophageal reflux, and constipation.⁴ The other two cases were worsened by the patient's history of milk protein allergy, recurrent eczema, and constipation. They were on a restricted diet due to multiple food allergies, indicating ongoing GI concerns.^5,6

Patients can also develop no symptoms. In one report, two patients did not have any gastrointestinal issues reported, although one Patient was seen for constipation at age 11.⁷

Behavioural and sensory issues

Children with Floating-Harbor Syndrome often exhibit behavioural and sensory issues that can complicate feeding. Sensory processing disorders are common in FHS and can lead to aversions to certain textures, tastes, and smells, making it difficult for children to accept a wide variety of foods. This can result in high restricted diet, increasing the risk of nutritional deficiencies. Behavioural feeding difficulties, such as food refusal or extreme picky eating, are also common. These behaviours can be exacerbated by the child's limited ability to communicate their preferences or discomforts due to speech delays.

In one child, the boy exhibited hyperkinesia, attention deficit, and episodes of aggression with minor frustrations.³ In another case, there were no specific behavioural issues reported, but sensory issues were hinted at by the presence of hirsutism and sensitivity to infections.⁴ Finally, a child developed attention deficits as reported by his kindergarten teachers. Sensory issues were not explicitly mentioned, but his speech and attention challenges could suggest underlying sensory processing difficulties.⁵

In one severe case, the patient exhibited a waddling gait and difficulty with lower limb strength. He also had urinary incontinence and bowel preparation needs. Post-operatively, the patient had residual motor function issues, including weakness in his right lower extremity and challenges with mobility.⁶

Nutritional challenges in FHS

The feeding challenges faced by individuals with FHS often lead to significant nutritional challenges. Maintaining an adequate and balanced diet is essential for supporting growth, cognitive development, and overall health. However, this can be difficult to achieve due to the complex interplay of physical, behavioural, and sensory issues.

Risk of malnutrition

Individuals with Floating-Harbor Syndrome (FHS) face a high risk of malnutrition due to feeding difficulties. Malnutrition in these patients can present as underweight, stunted growth, and deficiencies in vital vitamins and minerals. Such nutritional shortfalls can adversely affect a child’s development, leading to compounded issues with growth, cognitive function, and immune system strength.¹

In adult cases, early childhood feeding difficulties and poor weight gain indicate a potential risk for malnutrition. However, no ongoing malnutrition issues were reported later in life.² In children, frequent reports highlight malnourishment characterized by poor weight gain and a history of slow growth.^3,4,5,6

An additional complexity arises when considering a case where a child, initially malnourished, developed morbid obesity due to high-dose steroid treatment.⁶ This situation underscores the nuanced challenges in managing the nutritional needs of FHS patients.

Micronutrient deficiencies

Micronutrient deficiencies are a significant concern in individuals with FHS, particularly due to their restricted diets and feeding difficulties. Common deficiencies include iron, calcium, and vitamin D, all of which are crucial for growth and development. Iron deficiency, for example, can lead to anaemia, which can further impair cognitive development and physical stamina.

Calcium and vitamin D deficiencies can contribute to poor bone health, which is already a concern in individuals with FHS due to delayed bone age and short stature. In two cases, patients showed significant short stature and a markedly delayed bone age.⁷ The initiation of growth hormone therapy in this case suggests an increased risk of malnutrition and developmental issues, which may have been mitigated with appropriate nutritional interventions.

Diet modifications and supplements

Given the feeding and nutritional challenges associated with Floating-Harbor Syndrome, diet modifications and the use of nutritional supplements are often necessary to ensure that affected individuals receive adequate nutrition. Diet modifications may include the introduction of high-calorie, nutrient-dense foods to help address the calorie deficits caused by limited food intake. 

In some cases, specialized formulas or liquid nutritional supplements may be necessary, particularly if the individual has difficulty with solid foods or requires additional support to meet their nutritional needs. In two special cases, the child’s diet was modified due to milk protein allergy and included amino acid formula milk powder.^4,6 In another case, the child’s diet was adjusted to address allergies to milk, eggs, and carrots, resulting in a restricted diet that also included amino acid-based formula milk powder.⁵

Conclusion

Floating-Harbor syndrome (FHS) presents significant feeding and nutritional challenges due to oral motor dysfunction, gastrointestinal issues, and behavioural and sensory difficulties. These factors increase the risk of malnutrition and micronutrient deficiencies, impacting growth and development. Effective management requires diet modifications and nutritional supplements to address deficiencies and support overall health. A coordinated approach involving healthcare providers and caregivers is crucial for improving nutritional outcomes and quality of life for individuals with FHS.

FAQ’s

How can physical therapy aid in managing oral motor dysfunction in FHS?

Physical therapy can provide exercises to strengthen oral motor skills, improve coordination for chewing and swallowing, and support speech development, helping to mitigate some of the feeding and communication challenges.

Are there any specific educational accommodations recommended for children with FHS?

Educational accommodations may include individualised education plans (IEPs) addressing speech and language delays, sensory processing needs, and behavioural support to enhance learning and social interactions.

What are the implications of FHS for family planning and reproductive decisions?

Genetic counselling can provide valuable information for prospective parents about the risk of passing on FHS. Understanding inheritance patterns and available testing options can guide informed family planning decisions.