Diagnosis and management of tuberculosis in peritoneal dialysis

Abstract

Infectious complications represent the second cause of death in chronic renal failure, in particular tuberculosis (Tb), which remains more frequent in dialysis patients.
The aim of our work is to determine the prevalence of Tb in our patients on peritoneal dialysis (PD) and to analyze the clinical, paraclinical and evolutionary profile of this infection.
This is a retrospective cross-sectional study, including PD patients diagnosed with Tb. We analyzed their clinical and paraclinical profile, the diagnosis and localization of Tb, as well as the evolution under treatment.
We retained 12 cases of Tb among the 228 patients followed in PD (5.26%) from 2006 to 2022, with an M/F sex ratio of 0.7 and an average age of 52.7 ± 10 years. The median time between the start of PD and the diagnosis of Tb was 21 months [5 - 37].
The diagnosis of Tb was retained with certainty in 7 cases, based on bacteriological and/or histological evidence. The diagnosis was presumptive in 5 cases on a bundle of clinical and paraclinical arguments. The localization of Tb is pulmonary in 4 cases and extra-pulmonary in 8 cases including 3 cases of tuberculous peritonitis.
Anti-bacillary treatment is started after a median delay of 20 days [9-37] after the onset of symptoms. This treatment was complicated by 2 cases of drug-induced hepatitis and 1 case of polyneuritis.
The evolution is marked by healing in 11 patients. Regarding tuberculous peritonitis, the catheter was removed in one patient and maintained in the other two cases with favorable outcome.
In PD, the diagnosis of Tb is often difficult and extra-pulmonary involvement is more frequent.

INTRODUCTION

received 2023-03-28accepted 5/4/24 after ( revision 2023-04-06, published 2024-04-25

Peritoneal dialysis (PD) is an extrarenal purification method that can be offered as a first-line treatment for the management of stage 4-5 chronic kidney disease (CKD).

Infectious complications represent the second cause of mortality in dialysis patients, mainly Tb in our endemic context. This infection is often latent and can reactivate in dialysis patients. In Morocco, the annual incidence of Tb in the general population is 87 cases/100,000 inhabitants, and the isolated pulmonary form represents more than half of the cases[1]. In a Moroccan study, Bardai et al. noted 5 cases of Tb among 53 PD patients, i.e., a prevalence of 9.43%[2].

The clinical picture of Tb is often atypical, and bacteriological confirmation is difficult, making its diagnosis late.

The aim of our work is to determine the prevalence and location of Tb in our PD patients and to analyze the clinical, paraclinical, and evolutionary profile of this infection.

MATERIALS AND METHODS

This was a retrospective descriptive study, carried out in the PD unit of the Ibn Sina University Hospital in Rabat, Morocco, and covering a period from 2006 to 2022.

We identified 228 patients managed in the PD unit, and we retained only those patients who presented with a diagnosis of Tb.

From the medical records of the dialysis patients, we collected their personal history, the notion of Tb infection, and the functional signs reported by the patients, as well as the complete clinical examination.

We performed the biological and physiological workup in the patients and the search for Koch’s bacilli (BK) in biological fluids by direct examination in culture and by the polymerase chain reaction (PCR) of mycobacterial DNA (GeneXpert).

We specified the results of the radiological workup and the anatomopathological study of the biopsies performed for each patient.

The treatment protocol used included a quadruple combination for the first 2 months: rifampicin, isoniazid, ethambutol, and pyrazinamide, followed by a maintenance phase of 4 to 10 months, depending on the location of the Tb, based on a combination of rifampicin and isoniazid.

The dosage of antibacterial drugs was adapted to the weight of the patients and their dialysis status[3]. Residual rifampicin and isoniazid levels were routinely measured after the start of treatment. Adverse events were noted. Pyridoxine supplementation was systematic.

We described the short- and long-term evolution of our patients, based on clinical (fever, appetite, general condition, weight, dialysate fluid, etc.) and paraclinical (C-reactive protein, blood count, calcium levels, imaging, etc.) signs, as well as the side effects of antituberculosis drugs.

RESULTS

Of the 228 patients followed in the PD unit, 12 patients presented with Tb, a prevalence of 5.26%. The mean age of our patients was 52.7 ± 10 years with a male-to-female ratio of 0.7. The initial nephropathy was diabetic, vascular, indeterminate, tubulointerstitial, and glomerular nephropathy in 4, 3, 2, 2, and 1 case, respectively.

A history of relapsed pulmonary Tb was found in 1 patient, and the notion of Tb infection was reported in another patient in the family.

The median interval between the initiation of PD and the onset of clinical signs of Tb was 21 months (range[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]), with extremes ranging from 1 month to 5 years. In 4 patients, Tb was diagnosed during the first year of PD, representing 33.3% of patients.

Clinically, alteration in the general condition with fever and signs of Tb impregnation was present in almost all patients (92%). Signs of bacterial impregnation were evident in the majority of cases in the form of asthenia, night sweats, and weight loss of between 3 and 6 kg (83%).

Patients reported dyspnea in 4 cases, cough in 3 cases, chest pain in 2 cases, and hemoptysis in 1 case.

Clinical examination revealed a unilateral pleural effusion syndrome in 4 patients with peripheral adenopathies. On PD, the peritoneal dialysate fluid was cloudy in 3 cases.

Biologically, we observed an inflammatory syndrome in all patients with an elevated C-reactive protein level, hyperleukocytosis with lymphopenia, and hypoalbuminemia.

Radiologically, chest radiography was systematic in all patients, supplemented by a computed tomography (CT) scan in 7 cases, showing necrotic mediastinal adenopathies in 6 patients and excavated pulmonary nodules in 4 cases, including 1 case of miliary tuberculosis. At the serosal level, we noted unilateral pleurisy in 4 cases, pericarditis in 1 patient, and thickening of the peritoneal fat in 2 cases.

The abdominal CT scan showed necrotic abdominal adenopathy in 1 case.

Mycobacterium tuberculosis was tested in a total of 19 targeted samples. The analysis was positive in the sputum of 2 patients, in the dialysate fluid of 3 patients, and in the pleural fluid of 1 patient.

The analysis of pleural, pericardial, and bronchoalveolar fluids was found to be exudative and lymphocytic in nature in 5 cases, and the bacteriological investigation was negative.

The anatomopathological study of the 8 biopsies taken from the pleural, peritoneal, pericardial, and lymph node levels was in favor of Tb in only 2 cases (lymph node and peritoneal) after the demonstration of tuberculoid granuloma with caseous necrosis.

At the end of the clinical and paraclinical examinations, the diagnosis of Tb was retained with certainty in 7 cases based on bacteriological and/or

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