Clinical Characteristics of Pneumocystis Pneumonia After Parental Renal Transplantation

Abstract

Purpose: To analyze the clinical characteristics of Pneumocystis pneumonia (PCP) in renal transplant recipients, identify early sensitivity indicators, and optimize clinical strategies.

Patients and methods: We retrospectively analyzed clinical data for 24 patients with confirmed PCP who underwent renal transplantation (RT) between 2010 and 2019, encompassing a mean follow-up of 29 (range, 11-49) d.

Results: A 71% incidence was observed for PCP during the first 6 months after RT. Progressive dyspnea (79%) was the most common symptom, followed by fever (75%) and dry cough (67%). In the initial phase of PCP, the most frequent computerized tomography (CT) finding was the presence of symmetric, apically distributed ground-glass opacities. Nine of 11 patients (82%) were diagnosed by induced sputum testing, 14 of 17 (82%) by bronchoalveolar lavage, and 1 of 24 (4%) by sputum smear. The 1,3-β-D-glucan level was elevated (mean, 259.16 ± 392.34 pg/mL) in 80% of patients, while 75% had elevated C-reactive protein levels (median, 37.85 mg/L). Two of 18 patients (11%) were positive for cytomegalovirus. All patients were treated with trimethoprim-sulfamethoxazole (3 doses of 1-6 g/kg) and third-generation cephalosporin or moxifloxacin monotherapy to prevent bacterial infection. The methylprednisolone dose (40-400 mg/d) varied according to illness. Most patients were treated using a nasal cannula or oxygen mask, and 2 by mechanical ventilation. CT showed improved lesions after treatment, and completely absorbed lesions or residual fibrosis at follow-up. The mean hospitalization cost was 14,644.73 ± 11,101.59 RMB.

Conclusion: Peak PCP incidence occurred during the first 6 months after surgery. Progressive dyspnea, fever, and dry cough are important indicators for PCP. Bilateral and diffuse ground-glass opacities involving both lung apexes are often the first indication for PCP diagnosis. Induced sputum testing may be the method-of-choice for pathogen detection. The cure rate can be improved through early antipathogen, glucocorticoid, and preventive anti-infection therapies, as well as respiratory support.

Keywords: Pneumocystis jirovecii; clinical characteristics; optimize clinical strategies; renal transplantation.

Figure 1

Computed tomography (CT) showed ground-glass opacities in the apexes of both lungs in the initial phase of Pneumocystis pneumonia (PCP). (A) A 31-year-old male patient underwent parental-origin renal transplantation (RT) after 3 years of hemodialysis, and PCP occurred 7 months after RT. In the early stages, CT showed ground-glass opacities in the apexes of both lungs. (B) A 37-year-old female patient underwent RT after 8 years of hemodialysis, and PCP occurred 3 months after surgery. CT showed a decrease in the transmittance of the two lungs, and diffuse, plaque-like, and strip-like opacities were seen in both apexes. (C) A 30-year-old male patient underwent RT after 1 year of hemodialysis, and PCP occurred 3 months after RT. CT showed increased clouding and ground-glass opacities in the apexes of both lungs, and the edges were unclear. (D) A 39-year-old male patient underwent RT after 5 years of hemodialysis, and PCP occurred 3 months after surgery. CT showed ground-glass and strip-like, high-density shadows scattered across the apexes of both lungs.

Figure 2

Lung CT showed diffuse, plaque-like, ground-glass opacities in both lungs. (A) A 37-year-old male patient underwent RT after 4 years of hemodialysis, and PCP occurred 4 months after surgery. CT showed plaque-like, grid-like, high-density shadows and clouding in both lung fields, with blurred edges. (B) A 40-year-old female patient underwent RT after 1 year of peritoneal dialysis, and PCP occurred 5 months after surgery. CT showed increased multiple plaque-like opacities in the lungs, and the edges were unclear. (C) A 36-year-old male patient underwent RT after 1 year of hemodialysis, and PCP occurred 3 months after surgery. CT showed diffuse, ground-glass, high-density shadows in both lungs, with unclear edges. (D) A 34-year-old male patient underwent RT after 2 years of hemodialysis, and PCP occurred 4 months after surgery. CT showed scattered, plaque-like opacities in both lungs with unclear edges.