Primary Sjögren's syndrome (pSS) is characterized by lymphocytic infiltration of the exocrine glands resulting in decreased saliva and tear production. It uncommonly involves the kidneys in various forms, including tubulointerstitial nephritis, renal tubular acidosis, Fanconi syndrome, and rarely glomerulonephritis. Its clinical symptoms include muscle weakness, periodic paralysis, and bone pain due to metabolic acidosis and electrolyte imbalance. Herein, we describe the cases of two women with pSS whose presenting symptoms involve the kidneys. They had hypokalemia and normal anion gap metabolic acidosis due to distal renal tubular acidosis and positive anti-SS-A and anti-SS-B autoantibodies. Since one of them experienced femoral fracture due to osteomalacia secondary to renal tubular acidosis, an earlier diagnosis of pSS is important in preventing serious complications.
Acid-Base Equilibrium ; Acidosis ; Acidosis, Renal Tubular* ; Autoantibodies ; Diagnosis ; Exocrine Glands ; Fanconi Syndrome ; Female ; Femoral Fractures ; Glomerulonephritis ; Humans ; Hypokalemia ; Kidney ; Muscle Weakness ; Nephritis, Interstitial ; Osteomalacia ; Paralysis ; Saliva ; Tears

Autoimmune hemolytic anemia (AIHA) is a relatively common cause of anemia in children and adults with systemic lupus erythematosus (SLE). Although AIHA responds to steroids, in case of refractory or steroid-dependent AIHA, immunosuppressants and intravenous immunoglobulin have been used as second line agents. Rituximab, an anti-CD20 monoclonal antibody, is emerging in the treatment of SLE refractory to conventional therapy. Herein, we report a case of delayed and sustained remission of refractory hemolytic anemia in a child with SLE, post rituximab treatment. A 12-year-old female child with dizziness was referred to our department and was diagnosed with SLE combined with hemolytic anemia and renal tubular acidosis. Since frequent relapse of hemolytic anemia had occurred during the steroid tapering course, even though she had been treated with additional immunosuppressants (azathioprine, mycophenolate mofetil), the patient received 2 doses of rituximab 500 mg at 2 weeks interval at 18 months post diagnosis. After 15 months of rituximab administration, her anemia and renal tubular acidosis were fully recovered, enough to stop all medications. She remained well without recurrence for up to 3 years and 4 months after rituximab treatment.
Acidosis, Renal Tubular ; Adult ; Anemia ; Anemia, Hemolytic* ; Anemia, Hemolytic, Autoimmune ; Child* ; Diagnosis ; Dizziness ; Female ; Humans ; Immunoglobulins ; Immunosuppressive Agents ; Lupus Erythematosus, Systemic* ; Recurrence ; Steroids ; Rituximab

Distal renal tubular acidosis (RTA) caused by autoimmune nephritis occurs in up to 25% of patients with Sjögren's syndrome. However, patients with hypokalemic paralysis are sometimes overlooked, because most symptoms of autoimmune nephritis in Sjögren's syndrome are mild. We present a case of hypokalemic paralysis in a 54-year-old female who also had dry eyes and mouth, and Raynaud's phenomenon. Further evaluation, including autoantibody tests, revealed distal RTA with Sjögren's syndrome as the cause of hypokalemia. Distal RTA diagnosis was made based on normal anion gap hyperchloremic metabolic acidosis, alkaline urine with positive urine anion gap, high transtubular potassium concentration gradient (TTKG), positive anti-La antibody, and symptoms of sicca complex. The patient's symptoms resolved following treatment with intravenous and oral potassium, immunosuppressants, and steroids. This case illustrates that distal RTA and Sjögren's syndrome should be considered in cases of hypokalemic paralysis.
Acid-Base Equilibrium ; Acidosis ; Acidosis, Renal Tubular* ; Diagnosis ; Female ; Humans ; Hypokalemia ; Immunosuppressive Agents ; Middle Aged ; Mouth ; Nephritis ; Paralysis* ; Potassium ; Steroids

Acidosis, Renal Tubular ; diagnosis ; Female ; Humans ; Infant ; Mitochondrial Diseases ; diagnosis ; Seizures ; diagnosis

Although renal calcium crystal deposits (nephrocalcinosis) may occur in acute phosphate poisoning as well as type 1 renal tubular acidosis (RTA), hyperphosphatemic hypocalcemia is common in the former while normocalcemic hypokalemia is typical in the latter. Here, as a unique coexistence of these two seperated clinical entities, we report a 30-yr-old woman presenting with carpal spasm related to hypocalcemia (ionized calcium of 1.90 mM/L) due to acute phosphate poisoning after oral sodium phosphate bowel preparation, which resolved rapidly after calcium gluconate intravenously. Subsequently, type 1 RTA due to Sjogren's syndrome was unveiled by sustained hypokalemia (3.3 to 3.4 mEq/L), persistent alkaline urine pH (> 6.0) despite metabolic acidosis, and medullary nephrocalcinosis. Through this case report, the differential points of nephrocalcinosis and electrolyte imbalances between them are discussed, and focused more on diagnostic tests and managements of type 1 RTA.
Acidosis, Renal Tubular/*diagnosis/etiology ; Acute Disease ; Adult ; Antibodies, Antinuclear/blood ; Calcium Gluconate/therapeutic use ; Chronic Disease ; Female ; Humans ; Hydrogen-Ion Concentration ; Hypocalcemia/*chemically induced/complications/drug therapy ; Nephrocalcinosis/complications/*diagnosis/ultrasonography ; Parotid Gland/ultrasonography ; Phosphates/*adverse effects ; Salivary Glands/radionuclide imaging ; Sjogren's Syndrome/complications/*diagnosis/metabolism ; Submandibular Gland/ultrasonography

Primary renal lymphoma is one of the malignant lymphomas that initially presents in the extra lymphonode, which is rarely seen in children. This study reported two cases of primary renal lymphoma in children who were definitively diagnosed by renal biopsy. Renal tubular acidosis was the initial manifestation in both cases. They were referred to the hospital with chief complaints of polydipsia, polyuria, debilitation, vomiting and anemia. Imaging and laboratory examinations showed bilateral renomegaly, hypocalcemia, hypophosphatemia, and metabolic acidosis. One of the patients discontinued therapy. The other received chemotherapy including prednisone, vincristine, cytarabine and L-asparaginase, combined with intrathecal injections of methotrexate, dexamethasone and Ara-C and supporting treatment. Twenty-three days after treatment, polydipsia and polyuria were relieved, and acidosis, kaliopenia and anemia were improved in the patient. There were no abnormal findings in the renal B-ultrasound re-examination. It was concluded that when a patient is suspected of renal lymphoma, diagnostic puncture and renal biopsy should be performed early. Early combined therapeutics including chemotherapy, radiation therapy, surgery and supporting treatments may result in a favorable prognosis in patients with this disease.
Acidosis, Renal Tubular ; diagnosis ; etiology ; Child ; Humans ; Kidney Neoplasms ; complications ; Lymphoma ; complications ; Male

Acidosis, Renal Tubular ; complications ; diagnosis ; Child ; Diagnostic Errors ; Female ; Humans ; Medullary Sponge Kidney ; complications ; diagnosis ; Rickets ; diagnosis

PURPOSE: ARC syndrome refers to an association of arthrogryposis, renal tubular dysfunction, and cholestasis. The VPS33B gene was recently identified as the causative gene. So far, 41 cases of ARC syndrome have been reported worldwide, and it has rarely been reported in Korea. This study was conducted to report the clinical findings of seven ARC syndrome cases in Korean children, focusing especially on renal tubular dysfunction. METHODS: The hospital records of 7 cases diagnosed as ARC syndrome at Severance Hospital between Mar. 1995 and Aug. 2005 were reviewed and analyzed. RESULTS: Of the 7 cases, 4 were boys and 3 were girls. Six patients(85%) were born with normal birth weight at term, and one was born at preterm. All cases presented with cholestasis and severe jaundice. According to the type of arthrogryposis described by Brown et al, type 3 and 4 were found in 2 patients and type 6, 7, and the undistributed type in one patient respectively. Other associated clinical findings were as follows:failure to thrive in 6(85%), lax skin in 5(71%), and gray platelet syndrome in 4(57%). Urine analysis revealed 6 cases(85%) with proteinuria, 3(43%) with hematuria, 5(71%) with glycosuria, 2(29%) with phosphaturia and 2(29%) with calciuria. Serum electrolytes showed 4 cases(57%) with hyponatremia, 3(43%) with hypokalemia, and 1(14%) with creatinine elevation. Renal tubular dysfunctions were diagnosed as renal tubular acidosis in 6 cases(85%), nephrogenic diabetes insipidus in 2(29%), and Fanconi syndrome in 2(29%). During the follow-up period, 2(29%) had no treatment, 5(85%) had continuous supplementation to correct the electrolyte imbalance and acidosis, and 1(14%) had dialysis. Only one patient had a family history of ARC syndrome in a sibling. Four cases(57%) were diagnosed at the mean age of 8.2 months, and one case was lost during follow-up. Ages of the survived 2 cases were 13 and 25 months, respectively. CONCLUSION: The rare disease of ARC syndrome is associated with severe renal dysfunction. However, this study revealed that the renal manifestation of ARC syndrome in Korean children is relatively mild and survival rate is higher than that of previous studies. Contrary to previous reports, this study showed that familial cases are rare and sporadic occurence is possible in Korea. Thus, the diagnosis of this syndrome requires a careful evaluation of the renal function in cases of congenital arthrogryposis, and a mandatory genetic counseling of affected family for prevention of familial occurance.
Acidosis ; Acidosis, Renal Tubular ; Arthrogryposis* ; Birth Weight ; Child ; Cholestasis ; Creatinine ; Diabetes Insipidus, Nephrogenic ; Diagnosis ; Dialysis ; Electrolytes ; Fanconi Syndrome ; Female ; Follow-Up Studies ; Genetic Counseling ; Glycosuria ; Gray Platelet Syndrome ; Hematuria ; Hospital Records ; Humans ; Hypokalemia ; Hyponatremia ; Hypophosphatemia, Familial ; Jaundice ; Korea* ; Proteinuria ; Rare Diseases ; Siblings ; Skin ; Survival Rate

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 5:32 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 Na:Cl ratio on the average was 1:1.26 and for 33 patients below 1:1.35. 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 Na:Cl ratio, RTA should always be considered.
Acidosis ; Acidosis, Renal Tubular* ; Asthenia ; Diabetic Nephropathies ; Diagnosis ; Female ; Follow-Up Studies ; Humans ; Hypokalemia ; Lower Extremity ; Male ; Medical Records ; Medullary Sponge Kidney ; Nausea ; Paralysis ; Paresthesia ; Potassium ; Retrospective Studies ; Sjogren's Syndrome ; Urinary Calculi

PURPOSE: Renal tubular aicdosis (RTA) is a disorder of renal acidification out of porportion to the reduction in glomerular filtration rate. Type IV RTA refers to hyperkalemic metabolic acidosis resulting from aldosterone deficiency or resistance. The incidence of each type RTA has not been reported exactly, however reports on type IV RTA have been recently increasing. METHODS: A retrospective clinical analysis was performed in 50 patients with hyperkalemic distal renal tubular acidosis diagnosed between Jan. 1984 and Feb. 2003 at Department of Internal Medicine, Keimyung University, Dongsan Medical Center. RESULTS: From 1984 to 2003, 50 cases of hyperkalemic distal renal tubular acidosis were diagnosed. The mean age was 50.8+/-19.5 years. The two most common conditions were posttransplantation (28%), and diabetes mellitus (22%), which were followed by hypertension (12%), systemic lupus erythematosus (12%), chronic renal failure (12%), and others (26%). Asymptomatic hyperkalemia (34%), and muscle weakness (28%) were the two most common clinical presentations. All patients demonstrated normal anion gap acidosis with positive urine anion gap. The mean creatinine clearance was 25.6+/-16.4 mL/min. The mean baseline PRA and aldosterone levels were 3.82+/-7.16 ng/mL/hr and 110.02+/-108.2 ng/mL, respectively. Hyperkalemia was well responded to 9-alpha-fludrocortisone, furosemide, K-exchane resin, and combinations of these regimens. CONCIUSION: Type IV RTA is the most common type of RTA in children and adults, and can be an important cause of asymptomatic hyperkalemia. Therefore, type IV RTA should be included in the diffrential diagnosis of unexplained hyperkalemia in various clinical settings.
Acid-Base Equilibrium ; Acidosis ; Acidosis, Renal Tubular* ; Adult ; Aldosterone ; Child ; Creatinine ; Diabetes Mellitus ; Diagnosis ; Furosemide ; Glomerular Filtration Rate ; Humans ; Hyperkalemia ; Hypertension ; Hypoaldosteronism ; Incidence ; Internal Medicine ; Kidney Failure, Chronic ; Lupus Erythematosus, Systemic ; Muscle Weakness ; Retrospective Studies