Maki Shibata

The value of QuantiFERON®TB-Gold in the diagnosis of tuberculosis among dialysis patients

BACKGROUND It is difficult to diagnose tuberculosis (TB) in dialysis patients because of the high rate of extrapulmonary TB in these patients compared with the general population. Recently, a new diagnostic test called QuantiFERON (QFT) has been developed and shown promise as a diagnostic tool for active TB diseases and latent TB infection. METHODS We examined 162 dialysis patients admitted to a single institute, including 8 patients with active TB, and evaluated the utility of this test in dialysis patients. RESULTS Among 162 dialysis patients, positive QFT results occurred in 28 (17.3%), negative QFT results occurred in 95 (58.6%) and indeterminate QFT results occurred in 39 (24.1%). All eight active TB patients had positive QFT results, and none of the 95 patients with negative results had active TB. Among 23 patients with a history of active TB, 10 (43.5%) had positive results. Although the indeterminate rate was relatively high, no patient with an indeterminate result had active TB. Factors such as shorter duration of dialysis, lower lymphocyte count and higher white blood cell count were associated with indeterminate results. Among 105 cases after excluding the patients with previous TB or indeterminate results, the sensitivity of the QFT is 100% (8 of 8) and the specificity is 89.7% (87 of 97 cases). CONCLUSIONS Our data suggest that the QFT test is a useful supplementary tool for the diagnosis of active TB even in dialysis patients. Negative and indeterminate results on this test may be used to exclude the presence of active TB.

Antiepoetin antibody-related pure red cell aplasia: successful remission with cessation of recombinant erythropoietin alone

An elderly patient with pure red cell aplasia (PRCA) with antierythropoietin (anti-EPO) antibodies is described. PRCA due to alloimmunization is a rare and severe complication of recombinant human erythropoietin (rHu-EPO) therapy. Most reported patients with PRCA were cured primarily by immunosuppressive drug therapy. The patient in this case, however, did not want to receive any immunosuppressive drugs. Therefore, rHu-EPO injection was simply discontinued, the severe anemia gradually improved, and the hemoglobin approached normal range. This case is very rare and significant in that there have been few such elderly patients with rHu-EPO-induced PRCA in whom PRCA remission was achieved, with decreasing antibody titers, after cessation of rHu-EPO alone. Further cases are needed to assess how PRCA should be treated in patients with anti-EPO antibodies.

Factors associated with recovery of renal function in patients with multiple myeloma who were treated with hemodialysis.

Background: The presence of renal failure in patients with multiple myeloma (MM) has been considered an ominous prognostic factor associated with a significantly decreased life expectancy. The prognostic factors have seldom been analyzed to predict discontinuation of hemodialysis (HD) therapy in MM patients with renal failure after HD initiation. It is clinically very important to predict whether HD can be discontinued after introducing HD in such patients. Methods: All medical and HD records were reviewed in MM patients who underwent HD in the National Center for Global Health and Medicine Hospital between January 1995 and May 2009. Thirty-two patients with MM had undergone HD. The clinical features and the factors that might be associated with recovery of renal function leading to discontinuation of HD in MM patients with severe renal failure were examined. Results: The factors associated with recovery of renal function and discontinuation of HD were: low International Staging System (ISS) score (p = 0.0034); high response to chemotherapy (p = 0.036); low serum Ca (p = 0.006); low Cr (p = 0.019), and low serum β2-microglobulin (sβ2M) (p = 0.002). On multivariate analysis, low serum Ca and sβ2M were significantly associated with HD discontinuation. Moreover, discontinuing HD was the significant factor associated with improved overall survival in MM patients who required HD at least once. Conclusion: sβ2M and Ca were the laboratory parameters that were significant, independent prognostic factors for predicting the probability of recovery from severe renal failure and discontinuation of HD in MM patients who needed HD at least once.

Reduced Expression of Perlecan in the Aorta of Secondary Hyperparathyroidism Model Rats with Medial Calcification

Background. Vascular calcification is an important complication that worsens the prognosis for dialysis patients, although its detailed molecular mechanisms are still unknown. Methods. We produced a rat model for vascular calcification with hyperphosphatasemia and hyperparathyroidism, performing a 5/6 nephrectomy and providing a high-phosphorus, low-calcium diet for eight weeks. We examined mRNA obtained from the calcified aortae using microarray analysis, and searched for alterations in gene expression specifically in the calcified lesions. Results. Medial calcification was demonstrated in the abdominal aorta of 12 out of 42 hyperparathyroidism rats. In the aortae of hyperparathyroid rats with vascular calcification, the genes for heparan sulfate proteoglycans, including perlecan, were found to be down-regulated using microarray analysis and real time PCR. Immunohistochemistry also demonstrated reduced production of perlecan in the aortae of hyperparathyroid rats. Discussion. Perlecan is a major component of the vascular wall basement membrane and may play a role in protecting vascular smooth muscle cells from inflammatory cells and various toxins. It has also been reported that heparan sulfate chains may inhibit osteogenesis. Our findings indicate that perlecan may protect vascular smooth muscle cells from various factors that promote vascular calcification. Conclusions. It may be that reduced expression of perlecan in the calcified aortae of hyperparathyroid rats is a risk factor for vascular calcification.

A case of acute interstitial nephritis and granulomatous hepatitis induced by ingesting quinine

Quinine is used for the treatment of malarial infection, though not in common use. It is especially valuable for the parenteral treatment of severe illness owing to drug-resistant strains of Plasmodium falciparum. Quinine is also known to occasionally cause acute renal failure (ARF). Although quinine is listed in some reviews as a cause of acute interstitial nephritis, most cases of quinine-associated acute renal failure have been attributed to the hemolytic-uremic syndrome (HUS). Only two cases of acute renal failure due to acute interstitial nephritis associated with quinine have been reported [1, 2]. To our knowledge, there have been 6 reported cases of quinine-induced hepatic granuloma [3–8]. We report a case of quinine-induced acute interstitial nephritis (AIN) along with granulomatous hepatitis, both of which were confirmed on biopsy. A 50-year-old Nigerian man was admitted to the hospital with complaints of fever and general fatigue. He had been prescribed quinine as an antimalarial drug in a Nigerian hospital. The patient was febrile and showed nonoliguric ARF and liver dysfunction. In this case, liver injury showed gradual and spontaneous resolution after discontinuing quinine, and ARF resolved after treatment with oral prednisolone.

Large perinephric abscess in a patient on maintenance hemodialysis diagnosed by positron emission tomography combined with computed tomography (PET-CT).

Perinephric abscesses in patients on maintenance hemodialysis (HD) have seldom been reported. The case of a maintenance HD patient with a left perinephric abscess is reported. Although the lesion could not be visualized using other imaging examinations, using FDG and positron emission tomography combined with computed tomography (PET-CT), the patient was diagnosed as having a left perinephric abscess and nephrolithiasis. At the patients request, the perinephric abscess was treated conservatively with antibiotic therapy alone, and it eventually remitted. This is the first case report of a perinephric abscess diagnosed by FDG PET-CT in a patient on maintenance HD. FDG PET-CT appears to be useful for identifying perinephric abscesses in HD patients, resulting in early diagnosis and appropriate therapy for this severe infection.

Non-uniform Progression of Chronic Tubulointerstitial Nephritis and Widespread Nephrocalcification in a Patient with Anorexia Nervosa

Although patients with anorexia nervosa (anorexia) are known to show tubulointerstitial nephritis (TIN), the pathophysiology of its progression is not fully understood. We herein report a 31-year-old woman with anorexia who showed acute exacerbation of chronic kidney disease. Renal biopsy showed non-uniform chronic TIN; some areas were obsolete lesions and other areas were active lesions. In addition, many calcium-containing crystals were widely deposited in the distal tubules. The results suggest that chronic TIN in the setting of anorexia does not uniformly progress and that not only TIN but also widespread calcification of distal tubules might aggravate the renal function of anorexia patients.

Hereditary hemorrhagic telangiectasia in a patient with microscopic polyangiitis.

A 55-year-old Japanese woman with microscopic polyangiitis suffered repeated disturbance of consciousness and gastrointestinal bleeding. These problems were initially attributed to microscopic polyangiitis, but hereditary hemorrhagic telangiectasia was finally identified by further workup. Both microscopic polyangiitis and hereditary hemorrhagic telangiectasia are blood vessel-related diseases inducing similar symptoms. To our knowledge, this is the first observation of microscopic polyangiitis and hereditary hemorrhagic telangiectasia in the same patient. From a literature review of the clinical and pathologic manifestations of these diseases, a positive association may exist between the two diseases.