Peripheral smear showed normocytic normochromic red blood cells with diminished platelets. No immature cells were seen. Bone marrow aspiration showed erythroid preponderance with suspicion of subcortical physiological hypoplasia with 1- 2% ring sideroblasts. The myeloid: erythroid ratio was reversed to 1:3.4. Erythropoiesis was mildly megaloblastic with a moderate degree of dyserythropoeisis (<10%). Myelopoiesis showed maturation up to neutrophils. Megakaryocytes were diminished. Bone marrow biopsy revealed periosteum, cortex, and marrow spaces intervening the bony trabeculae. A reduced cellularity for age with overall cellularity of 40-45% was noted. There was erythroid preponderance with a mildly megaloblastic reaction. Myelopoiesis showed maturation up to neutrophils. Few megakaryocytes with normal morphology and topography were present. Myelogram showed: Neutrophils-08%, Metamyelocyte-04%, Myelocyte- 04%, Promyelocyte-01%, Blast-00%, Eosinophil-00%, Monocyte-00%, Lymphocyte-23%, Plasma cells-02%, Erythroid cells-58%. Flow cytometry showed a PNH clone within the neutrophils (25.6%) and monocytes (30.3%).

The patient had a full HLA match with her sister (10/10). CT scan venogram brain showed no significant abnormality. There was no evidence of any deep venous thrombosis. Also, the blood parameters and the symptoms remained unchanged in spite of multiple blood transfusions.

The patient was then admitted to the bone marrow transplant unit with a neutropenic diet [3]. Her body weight, vital signs, input, and output were monitored twice daily. Protocols for thrombocytopenic precautions like avoidance of aspirin therapy and intramuscular injections were followed. Irradiated blood components were advised. A peripherally inserted central catheter was placed and a conditioning regimen of Busulphan-Cyclophosphamide for PNH was started including antimicrobial, antiemetic, seizure, and veno-occlusive prophylaxis via the infusion pumps. Injection Busulfan 150 mg (3.2mg/kg) intravenous infusion was given on day -4. Injection cyclophosphamide 2900 mg (60mg/kg) from day –3 to day –2 and Injection Ifosfamide 3000 mg was administered from day-3 to day-2.

The donor had arrived from overseas, therefore, Covid – 19 RT-PCR testing was done as part of routine Indian - International air travel guidelines [4]. The donor came out to be Covid – 19 RT-PCR negative. The PBSC was planned two weeks after her arrival. The RT-PCR test was repeated before admission as part of the Institutional protocol and this time the donor was found to be SARS- CoV- 2 positive but without any symptoms.

As the patient had already received myeloablative conditioning, based on risk-benefit analysis, transplantation was a must. The initial plan for bone marrow harvesting was deferred as the procedure had to be done as an inpatient basis inside an operation theatre. Therefore, in a multidisciplinary meeting consisting of specialists from hematology, transfusion medicine, infection control, COVID nodal officer, and management, it was consensually decided on a PBSC harvest which was to be performed in a COVID isolation unit.

The donor was of A positive blood group and the patient was of O positive blood group. The anti-A titer was 1:32. Injection Filgrastim 600 mcg[10mcg/kg] S/C was administered every day from day -4 to day 0 one week before harvesting. An informed written consent was taken from the donor before the stem cell harvest. Considering the procedure was being performed on a SARS- CoV- 2 positive donor, special precautions and all personnel protective equipment (PPE) were used in accordance with the infection control policy.

Allogeneic stem cell harvest was performed under aseptic procedures using Spectra Optia Apheresis System (Lakewood, Colorado 80215, USA). After processing a total blood volume of 10280 ml, a CD 34 count of 2170 cells/microliters with a product volume of 210 ml was obtained. A product yield of 9.53 million cells/kg was obtained. The total time taken for the procedure was 1 hour and 861 ml of acid citrate dextrose (ACD) was used for anticoagulation. Intravenous calcium replacement was given prophylactically at a dose appropriate to the donor’s body weight to prevent hypocalcemia due to citrate-related toxicity.

The patient was administered the stem cell product on the same day of collection and she tolerated the procedure well on 18/12/2021 [day 0] without any adverse events. She was also closely monitored to look for any signs or symptoms suggestive of SARS- CoV- 2 infection. The patient stayed in an isolation unit after transplantation and was also checked once a week with RT-PCR for SARS CoV-2 and her COVID-19 PCR status remained negative on 15/12/2021,20/12/2021 and 27/12/2021. Her Graft Vs Host disease (GVHD) prophylaxis consisted of I. V Cyclosporine 150 mg (3mg/kg) which started on day+ 2 along with a short course of methotrexate 15mg/m2 on day+1. This was followed by 10mg/m2 on day +3,+6 and +11. No features of GVHD were observed in the patient.

Her hematological recovery was seen from day +11 onwards. The neutrophil engraftment of ANC>500 cells/uL was achieved on day +11. Her WBC count reached >1000 cells/uL on day +12 and platelet >20,000/mm3 on three consecutive days was met from day +15. The patient was discharged on 2/01/2022 in a stable condition.

Since the outbreak of the omicron variant of covid 19, genotyping of all international patients affected with SARS- CoV- 2 was done as a protocol in India. Since this sequencing was performed by Government authorities, a report of the exact variant was unavailable at the time of writing the report by the authors.