Case report of peritoneal carcinomatosis of plasma cell origin in a patient with newly diagnosed HIV: A terminal event

Background B-cell tumors and plasma cell malignancies have been identified in persons living with the human immunodeficiency virus (PLHIV). The literature review has revealed numerous reports of solitary plasmacytomas with metastasis in PLHIV. Case report A young patient with no prior medical or surgical history presented with tumor lysis syndrome secondary to metastatic plasma cell Epstein-Baer virus (EBV) related malignancy with peritoneal carcinomatosis. The history and clinical picture promptly led to the diagnosis of HIV. The subsequent hospital course was dismal, and lifespan was cut short by multi-organ failure. Conclusion This case is being reported to highlight the suspicion of HIV in patients presenting acutely with aggressive plasma cell malignancies.


Introduction
Due to the advent of combination antiretroviral therapy (cART), leading to the effective management of HIV complications, the overall survival of persons living with human immunodeficiency virus (PLHIV) has increased [1]. The general incidence of acquired immunodeficiency syndrome (AIDS) defining malignancies has been decreasing significantly after the introduction of (cART) as well [2]. However, several non-AIDS-defining malignancies are rising due to concurrent exposure to other carcinogens and patient-related factors. The association of HIV with malignancies, in particular plasma cell tumors, is well established. Sporadic cases of plasma cell proliferation disorders have been reported in recent years. We present a case of a young male who was found to have an aggressive hematological malignancy on initial presentation, which was found to be a plasma cell neoplasm on lymph node biopsy. He was subsequently found to have advanced HIV infection. The case is being reported to suspect HIV is a widely metastatic plasma cell disorder along with other AIDS-defining malignancies (Sarcoma, non-Hodgkin lymphomas, and cervical cancer).

Case presentation
A 33-year-old African American male with no prior medical or surgical history except for recent hemorrhoids presented to the emergency room of New York City in the second half of 2020 with three months of abdominal distention, nausea, non-bloody vomiting, and weight loss. He also reported pleuritic chest pain, which was localized to the lower chest bilaterally. A review of systems was positive for weight loss, constipation, and hematochezia. He denied any fevers, chills, The patient reported a recent episode of shingles around his eye and a fall without any loss of consciousness on further inquiry. His social history was significant for unprotected sex with multiple male partners. The patient denied intravenous drug use, smoking, alcohol, or illicit drug use. He was never diagnosed or treated for a sexually transmitted infection (STI). The patient was not following with his primary care doctor, and his family history was remarkable for his mother having Factor 5 Leiden mutation with an episode of pulmonary embolism.

AIDS Research and Therapy
The patient was hemodynamically stable on admission (blood pressure 126/82 mmHg, heart rate 70 beats per minute, respiratory rate 16 breaths per minute, temperature 96.8 F, saturating 95% on room air). On physical exam, the patient appeared chronically ill and cachectic with temporal wasting. A small painless, immobile, nodular mass was noted on the right side of the chest wall. The abdomen was distended, and bilateral lower extremity edema was noted. The patient was documented to weighed 67 kg on arrival with a BMI of 20.7 kg/m2 (baseline found to be 120 kg as per the patient).
Iron studies showed anemia of chronic inflammation. Hepatitis panel was reactive for Hepatitis C, QuantiF-ERON-TB Gold Plus (Qiagen) testing resulted as indeterminate. Toxoplasma IgG and IgM, EBV IgM, and early antigen were negative. EBV IgG and virus capsid antigen, nuclear antigen was positive, and the EBV viral load was 50,900 IU/mL. Cytomegalovirus (CMV) IgG also tested positive.
Tumor markers were obtained (Table 2). Paraproteinemia with increased M-spike was seen on SPEP. UPEP was found within normal limits (Table 3). Serum immunofixation showed elevated IFE lambda 6.48 mg/   Excisional biopsy of the right chest wall mass, a probable lymph node 1 × 2 cm, was performed for tissue diagnosis, which showed plasma cell neoplasm with pleomorphic morphology, focal necrosis, and high ki-67. Atypical cells were reported as plasmacytoid with eosinophilic cytoplasm, which was pleomorphic and large with a multinuclear, mixed population of kappa light chain restricted plasma cells.
The patient responded to volume resuscitation initially but remained tachycardiac and hypotensive, further complicated by acute respiratory failure. D-dimer was elevated; pulmonary embolism could not be ruled out considering the history of Factor V mutation in his mother. CT angiogram of the chest was not performed given AKI, and he could not be started on anticoagulation owing to low hemoglobin and hematochezia. Echocardiogram was negative for right heart strain. The lower extremity venous duplex was negative for any deep venous thrombosis.
The patient continued to worsen over 72 h and was intubated on day 4 of hospitalization, requiring vasopressor support and renal replacement therapy. The medical team discussed goals of care and advanced directives with the family, who expressed their wishes not to resuscitate the patient in the event of cardiac arrest. The patient expired on day 5 of hospitalization secondary to cardiopulmonary arrest.

Discussion
HIV infection complicated by immunosuppressed state defined as AIDS predisposes individuals to malignancies, commonly B cell lymphomas [3][4][5]. A handful of malignancies are categorized as AIDS-defining malignancies per the world health organization (WHO) classification to emphasize the causation and highly suspect underlying HIV infection if these malignancies are reported [6]. Plasma cell malignancies in PLHIV are rare but have been reported since the 1980s, including the rare plasmablastic lymphomas. The incidence has been on the rise, especially in cases with coinfection with EBV, a known oncogenic virus and causes unchecked proliferation of B cells. Most plasma cell proliferation is associated with light chain immunoglobulins. Some cases are observed to be highly responsive to cART if caught earlier in the timeline of malignant transformation [7]. Paraproteinemia has been reported in the cohort of PLHIV, pointing towards increased plasma cell proliferation in these patients [8][9][10][11][12][13]. Multiple myeloma has been seen in HIV-positive patients from a broad spectrum of presentations, from having chronic lymphadenopathy to multiple extramedullary plasmacytomas and osteolytic bone lesions.
The association of plasmacytomas with HIV has been well established. HIV-associated plasmacytomas have been seen in extramedullary sites as well as rare primary sites, including mesentery [14], ureter [15], and laryngeal   wall [16], and also as a mass in the kidney [17]. Plasma cell disorders in such immunosuppressed populations are often severe with a noticeably short aggressive clinical course and in a younger patient population compared to the typical age group affected by plasma cell malignancies.
A case of plasmablastic lymphoma with a similar case presentation as ours was reported, including widespread malignancy involving the peritoneal cavity as well, but that particular patient was immunocompetent and tested negative for HIV [18]. This case, and the existing literature, highlight the importance of considering a diagnosis of HIV infection in the setting of plasma cell malignancies.

Conclusion
About our case presented, all this evidence-based data points out that HIV, especially when undiagnosed with an exceedingly high viral load, compounded by oncogenic viral coinfections, predisposes an individual to plasma cell malignancies. The manifestation has been increasing since the initial publication in 1983 and has not been incidental. The presence of multiple myeloma, paraproteinemia, widespread aggressive malignancies should prompt an investigation to rule out HIV infection. Timely diagnosis and treatment in younger populations might prevent the essentially terminal prognosis.