Cystic_Fibrosis_Features_Flashcards
What are the presenting features of cystic fibrosis in the neonatal period?
Meconium ileus (around 20%), less commonly prolonged jaundice.
What are the presenting features of cystic fibrosis in childhood?
Recurrent chest infections (40%), malabsorption (30%): steatorrhoea, failure to thrive, other features (10%): liver disease.
What percentage of cystic fibrosis patients are diagnosed after the age of 18 years?
Around 5% of patients are diagnosed after the age of 18 years.
What are other features of cystic fibrosis?
Short stature, diabetes mellitus, delayed puberty, rectal prolapse (due to bulky stools), nasal polyps, male infertility, female subfertility.
summarise CF features
Cystic fibrosis: features
Presenting features
neonatal period (around 20%): meconium ileus, less commonly prolonged jaundice
recurrent chest infections (40%)
malabsorption (30%): steatorrhoea, failure to thrive
other features (10%): liver disease
Whilst many patients are picked up during newborn screening programmes or early childhood, it is worth remembering that around 5% of patients are diagnosed after the age of 18 years.
Other features of cystic fibrosis
short stature
diabetes mellitus
delayed puberty
rectal prolapse (due to bulky stools)
nasal polyps
male infertility, female subfertility
A 15-year-old female visits her GP because she is feeling increasingly tired and losing weight. She has also been urinating more frequently and feeling extremely thirsty. Random plasma glucose is found to be 15 mmol/litre.
The patient has an underlying condition diagnosed from childhood, which has caused the development of these symptoms. Which of the following is most likely to be the underlying condition?
Congenital adrenal hyperplasia
Cystic fibrosis
Hyperthyroidism
Juvenile idiopathic arthritis
Iron deficiency anaemia
Cystic fibrosis
Cystic fibrosis can cause diabetes mellitus
This presentation is a classic description of the onset of diabetes in a young person, and is confirmed by the random blood glucose >11mmol/L.
Out of the options available, only cystic fibrosis can cause the development of diabetes. Cystic fibrosis presents in childhood with respiratory symptoms, but as the disease progresses, further features begin to develop. If the pancreas becomes affected, then diabetes mellitus can develop. It can take time for the pancreas to be affected enough to cause diabetes, which is why children with cystic fibrosis may develop diabetes later in life.
The other conditions may cause fatigue or weight loss, but not polyuria or polydipsia.
After a positive heel prick test for cystic fibrosis, a newborn baby is sent for further genetic testing which confirms the diagnosis. The parents are very concerned about the potential implications of the disease for their child.
What is a recognised complication of this condition?
Bicuspid aortic valve
Cystic hygroma
Diabetes mellitus
Hypothyroidism
Meckel’s diverticulum
Diabetes mellitus
Cystic fibrosis can cause diabetes mellitus
Diabetes mellitus is correct. Cystic fibrosis is a genetic disorder that impacts the secretory glands, including those producing mucus and sweat. It’s most well-known for causing recurrent lung infections and difficulty breathing over time. However, it can also affect other systems in the body. One of these complications is cystic fibrosis-related diabetes. This form of diabetes is unique to people with cystic fibrosis and is caused by the thick mucus damaging the pancreas, limiting insulin production.
Bicuspid aortic valve is incorrect. There is no association between cystic fibrosis and bicuspid aortic valve. This abnormality is however associated with Turner’s syndrome, another genetic disorder.
Meckel’s diverticulum is incorrect. There is no link between this congenital abnormality and cystic fibrosis. Meconium ileus- an obstruction of the small bowel due to thick and sticky stool, is a recognised complication of cystic fibrosis.
Cystic hygroma is incorrect. A cystic hygroma is a fluid-filled sac commonly found in the neck, due to a malformation in the lymphatic system. There is no association with cystic fibrosis.
Hypothyroidism is incorrect. Hypothyroidism is not a recognised complication of cystic fibrosis.
