An Unusual Case of Pneumocystis jirovecii Cystic Pneumonia

Dear Editor, Pneumocystis jirovecii pneumonia is severe form of pneumonia seen in immunocompromised persons. It is caused by P. jirovecii a unicellular, obligate fungus. It has two morphological types': the cystic and trophozoite forms. Its incidence has decreased in patients with human immunodeficiency virus (HIV) after the introduction of antiretroviral therapy. Clinical presentation in HIV patients constitutes a triad of symptoms including dry cough, dyspnea, and low-grade fever. Typical radiological features include bilateral ground-glass opacities with nodules and peripherally placed lung cysts.1,2 A 41-year-old female with no prior comorbidities or medications was admitted with a history of intermittent low-grade fever up to 101°F, dry cough, and gradually progressive shortness of breath for 4 months. She also reported a significant loss of weight and appetite over this period of illness. She took treatment from the local hospital and had a slight resolution in her symptoms. She again had worsening of symptoms with progression of shortness of breath to modified Medical Research Council Grade IV for the last 10 days. On evaluation, she had systolic blood pressure of 130 mmHg, diastolic blood pressure of 80 mmHg, pulse rate of 130 per min, respiratory rate of 24 per min, and oxygen saturation of 98% on 15 L/min of oxygen support. Contrast-enhanced computed tomography of the chest showed bilateral diffuse ground-glass opacities with scattered patchy areas of consolidation Figure 1a-d thin arrows along with multiple lung cysts Figure 1a-d solid arrows. She was also diagnosed to be HIV-1 positive by enzyme-linked immunosorbent assay with CD4 count of 24 cells/mm3. Differential diagnosis of P. jiroveci pneumonia and cytomegalovirus (CMV) pneumonia was kept in view of the immunocompromised status. Laboratory investigation showed hemoglobin of 12.2 g/dL, total leukocyte count of 8750/μL, platelet count of 348,000/μL, C-reactive protein of 15.7 mg/L, and raised lactate dehydrogenase (LDH) of 657 IU/L. She was started on injection trimethoprim–sulfamethoxazole intravenous thrice a day and methylprednisolone twice a day for 3 days in view of severe hypoxia (SPO2 of 83.3%), followed by oral trimethoprim–sulfamethoxazole double strength thrice a day and oral prednisolone 40 mg twice a day, followed by recommended tapering dose. Later on, investigations showed raised beta-D-glucan of 142 pg/mL. She had resolution in her symptoms and was subsequently discharged home without any oxygen support.Figure 1: (a-d) Computed tomography of chest showing bilateral diffuse ground-glass opacities (thin arrows) with scattered patchy areas of consolidation and bilateral lung cysts of varying sizes (solid arrows)P. jirovecii pneumonia is severe form of fungal lung infection due to P. jirovecii seen commonly in immunocompromised hosts. After the introduction of antiretroviral therapy, there has been gradual decline in cases of P. jirovecii in HIV patients with increases in patients on immunosuppressive therapies for cancer and solid organ transplant. Clinical presentation may vary from nonspecific symptoms such as low-grade fever and cough to severe rapidly progressive dyspnea over few days.1,2 Typical radiological features are diffuse bilateral interstitial pneumonia with ground-glass opacities, nodules, and bilateral lung cysts in few patients. Differential diagnoses include tuberculosis, CMV pneumonia, drug-induced pneumonia, radiation pneumonitis, eosinophilic pneumonia, and severe viral pneumonia.3 In patients with P. jirovecii pneumonia, lung cysts typically are multiple, mostly in the upper lobes, and resolve with adequate treatment. Mortality in severe cases varies from 10% to 20% in HIV cases to 30%–60% in other immunocompromised cases without HIV.1 Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal her identity, but anonymity cannot be guaranteed. Research quality and ethics statement Authors followed applicable EQUATOR Network (https://www.equator-network.org/) guidelines, notably the CARE guideline, during the conduct of this report. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.