Clinical manifestations of cystic fibrosis among patients with diagnosis in adulthood.
OBJECTIVE
To define the clinical characteristics and diagnostic parameters of patients with cystic fibrosis (CF) diagnosed in adulthood.


METHODS
Retrospective cohort study.


METHODS
Tertiary care center.


METHODS
All patients with a diagnosis of CF made at the Toronto CF Clinics between 1960 and June 2001. Data were collected prospectively and analyzed retrospectively.


RESULTS
There were 73 of 1,051 patients (7%) with CF diagnosed in adulthood. Over time, an increasing number and proportion of patients received a diagnosis in adulthood: 27 patients (3%) before 1990, compared to 46 patients (18%) after 1990 (p < 0.001). The mean sweat chloride level was lower for those with CF diagnosed as adults, compared to those with a diagnosis as children (75 +/- 26 mmol/L and 100 +/- 19 mmol/L, respectively; p < 0.001) [mean +/- SD], and adults were more likely to have pancreatic sufficiency (PS) than children (73% vs 13%, respectively; p < 0.0001). In 46 adults who received a diagnosis since 1990, the reason for the initial sweat test was pancreatitis (2 patients, 4%), pulmonary symptoms (18 patients, 39%), pulmonary and GI symptoms (10 patients, 22%), infertility (12 patients, 26%), and genetic screening (4 patients, 9%). Other manifestations were biliary cirrhosis (one patient) and diabetes mellitus (four patients, 9%). The diagnosis could be confirmed by sweat test alone in 30 of 46 patients (65%), by mutation analysis alone in 15 patients (33%), and by a combination in 31 patients (67%). Nasal potential difference (PD) measurements alone confirmed the diagnosis in the remaining 15 patients (33%).


CONCLUSIONS
Patients with CF presenting in adulthood often have PS, inconclusive sweat test results, and a high prevalence of mutations that are not commonly seen in CF diagnosed in childhood. Although most patients have lung disease of variable degrees, single-organ manifestations such as congenital bilateral absence of the vas deferens and pancreatitis are seen. Repeated sweat tests and extensive mutation analysis are often required. Nasal PD may aid the diagnosis, but has not been standardized for clinical diagnosis.
Gilljam
Marita
M
Department of Respiratory Medicine and Allergology, Sahlgrenska University Hospital, Goteborg University, Goteborg, Sweden.
Ellis
Lynda
L
Corey
Mary
M
Zielenski
Julian
J
Durie
Peter
P
Tullis
D Elizabeth
DE
D000328:Adult; D003550:Cystic Fibrosis / Q000175:diagnosis*; D004252:DNA Mutational Analysis; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D012965:Sodium Chloride / Q000032:analysis; D013542:Sweat / Q000737:chemistry
D012965:Sodium Chloride