Diversity of initial manifestations in renal tubular acidosis / 대한내과학회지

ABSTRACT

BACKGROUND: Diagnosis of RTA (renal tubular acidosis) is not easy due to its nonspecific and various manifestations. To find out the clues to diagnosis, we investigated initial manifestations, laboratory features and clinical course of RTA patients. METHODS: Thirty-seven patients with RTA type I or II, whose follow-up period was over 6 months were included in the study. We reviewed their medical records retrospectively. RESULTS: Male to female ratio was 532 and the average age at the time of diagnosis was 38.7 (15~60). Twenty-five patients had RTA type I, nine had type II, and three had both. The average follow-up period was 6.4 years. Initial manifestations were asthenia (54%), nausea (46%), urinary stone (24%), paresthesia (24%), lower extremity weakness (22%), and paralysis (11%). Underlying diseases at the time of diagnosis include Sjogren's syndrome (14%), SLE (8%), drug-induced nephropathy (11%), diabetic nephropathy (5.4%), Sjogren's syndrome combined with SLE (2.7%), and medullary sponge kidney (2.7%). Laboratory tests revealed acidosis with hypokalemia (59%), acidosis without hypokalemia (14%), and hypokalemia without acidosis (24%). The level of total CO2 was 22 mmol/L or lower in 27 patients. The NaCl ratio on the average was 11.26 and for 33 patients below 11.35. Renal function deteriorated in 8 patients and 7 of them had underlying diseases. Urinary stone developed in 2 patients with RTA type I. CONCLUSION: When patients with nonspecific symptoms show decreased levels of serum total CO2, potassium, or NaCl ratio, RTA should always be considered.