Journal of Pediatric Critical Care

P - ISSN : 2349-6592    |    E - ISSN : 2455-7099

Critical Thinking
Year : 2019 | Volume : 6 | Issue : 3 | Page : 81 - 84

PICU QUIZ - Hematology

Nikhil Vinayak1, Pradeep Kumar Sharma2

1Consultant, 2Senior Consultant and Head, Pediatric Critical Care and Pulmonology, Sri Balaji Action Medical Institute, New Delhi, India.

Correspondence Address:

Dr. Pradeep Kumar Sharma,Senior Consultant and Head,
Pediatric Critical Care and Pulmonology, Sri Balaji action Medical Institute, New Delhi.
Mob.: +91-9868797049, Email: drsharma025@gmail.com
Received:20-Apr-19/ Accepted: 02-May-19/Published Online:05-Jun-19

Source of Funding:None Conflict of Interest:None

DOI:10.21304/2019.0603.00511


Q. 1:
A 4-year-old child, a case of severe dengue is referred to your center from outlying hospital. At admission child is having a respiratory rate of 55/ min, moderate intercostal retractions, bilateral air entry is decreased and SpO2 is 92% on room air. Heart rate is 120/min, peripheral pulses are low volume and blood pressure is 90/72 mm Hg. Over the course of 4 days child’s condition improves, he becomes hemodynamically stable and respiratory distress settles. However, on Day 6 child develops new onset of continuous high-grade fever. Laboratory investigations show a hemoglobin 7 gm%, total leukocyte count 1.2 x 109/L, platelet count 45,000/ mm3, SGOT 500 IU/L, SGPT 487 IU/L, total bilirubin 2 mg/dL, serum triglycerides 300 mg/dl, fi brinogen 1 gm/L, serum ferritin 5000 μg/L. Bone marrow examination shows hemophagocytosis. Which of the following statements about Hemophagocytic lymphohistiocytosis (HLH) is not true:
a) Older age and presence or absence of infection cannot be used to rule out primary HLH.
b) Soluble IL2r are markedly increased in HLH
c) Serum ferritin levels >10,000 μg/L in pediatric population is highly sensitive and specifi c (>90%) for HLH
d) Hemophagocytosis is pathognomic for HLH and the number of hemophagocytes on biopsy specimen refl ects clinical activity.
e) There is insuffi cient data to determine which patients with secondary HLH need full HLH 2004 treatment protocol.

Q. 2:
A 5-year-old boy is admitted with complaints of fever for 10 day, headache, blurred vision and slurred speech for 1 day. His heart rate is 100/min, BP is 90/50 mm Hg, pulses are good volume, respiratory rate is 25/min, SpO2 is 97% on room air and GCS is 15. Laboratory values are: TLC 480 x 109/L; hemoglobin 5.8gm%; platelets 30000/mm3; sodium 146meq/L; potassium 3.8 meq/L; blood urea nitrogen 18 mg/dL; creatinine 0.45 mg/dL. Smear shows a predominance of blasts. Which of the following is the most appropriate plan of action to relieve his symptoms?
a) Immediate transfusion of packed RBCs
b) Immediate initiation of hyper-hydration therapy with diuretics
c) Start Leukapheresis
d) Start corticosteroids
e) Start Mannitol

Q. 3:
You have a 7-year male who comes in with history of fever for 10 days, easy bruising, pallor, and fatigue for 5 days. CBC reveals a WBC of 380 x 109/L with 50% blasts, Hb of 6.5 gm%, and platelets of 15000/mm3. He is tachypneic to a respiratory rate of 45, has had diminished urine output, and demonstrates some confusion and listlessness. Which of the following would generally be contraindicated in his acute management?
a) Steroids
b) Hydroxyurea
c) Fluid boluses
d) PRBC transfusions
e) Platelets transfusion

Q. 4:
You have a 3-year patient who comes in with new onset AML. She has a moderate oxygen requirement (3 liters/min through nasal cannula) and appears lethargic. A diagnosis of leukostasis is made. There is no evidence of tumor lysis and the decision is made to proceed with leukapheresis. Post-leukapheresis, her CBC reveals a WBC of 30 x 109/L (from 150 x 109/L pre-leukapheresis), Hb 8.5, and platelets of 18000/mm3. Her oxygen requirement is stable and her respiratory distress appears somewhat improved. She is also more alert and responsive. Tumor lysis labs reveal a K of 4.7 meq/l and a uric acid of 4.5 mg/dl. Which one of the following therapies is indicated?
a) Rasburicase
b) Allopurinol
c) Calcium Chloride
d) pRBC transfusion
e) Platelet Transfusion

Q. 5:
A 10-year girl who was previously well, has been admitted to your ICU with vomiting, malaise and decreased urine output. She has a new diagnosed Burkitt lymphoma and received her fi rst round of chemotherapy four days ago. The following blood results were obtained: serum potassium 5.5 meq/L; phosphate 9 mg/dl, corrected calcium 5.5 mg/dl, uric acid 10 mg/dl, urea 45 mg/dl and creatinine 1 mg/dl. Which of the following statements is true?
a) Rasburicase and allopurinol combination therapy has been found to rapidly lower serum uric acid levels.
b) A high urine pH can lead to uric acid and calcium phosphate crystallization and nephropathy
c) Above patient should be given calcium gluconate
d) Phosphate removal is best achieved by CRRT in established TLS
e) Alkalization of urine and rasburicase should be started

Q. 6:
A 5-year-old child was admitted with life threatening shock after being involved in a motor vehicle accident. He suffered extensive limb and thoracic injuries requiring emergency surgery. Intra operative course was complicated by major blood loss and haemodynamic instability. Post operatively following return to ICU, he was noted to become hypotensive and febrile and oozy from various drip and operative sites. Red urine was noted. The following were the laboratory tests: Hb 8 gm%, TLC 18.9 x 109/L, platelets 127 x 109/L, urea 24 mg/dl, creatinine 0.6 mg/dl, creatinine kinase 2000U/L, urine myglobin trace, urine hemoglobin ++. Based on his clinical history and the lab report, what is the likely cause of his post operative deterioration?
a) Rhabdomyolysis
b) Hemorrhagic shock
c) Mismatched transfusion
d) Septic shock

Q. 7:
Which of the following statement is true for both Transfusion-related acute lung injury (TRALI) and Transfusion-associated circulatory overload (TACO):
a) TRALI and TACO both result in non-cardiogenic pulmonary edema
b) TRALI and TACO both have symptoms of hypoxemia and bilateral lung infi ltrates
c) TRALI and TACO are both antibody mediated processes
d) TRALI and TACO both result in pulmonary edema which responds acutely to diuretics
e) TRALI and TACO both rarely occur in pediatric hematology and oncology patients, and should be on the differential diagnosis only when pulmonary complications arise at least 12 hours after transfusion of any blood product

Q. 8 :
In children with acute leukemia and complications requiring mechanical ventilation which of the following is associated with the worst survival rate in clinical studies.
a) Severity of illness as measured by PRISM score
b) The presence of sepsis
c) Duration of mechanical ventilation
d) A high-risk classifi cation of leukemia
e) A diagnosis of acute myeloid leukemia

Q. 9:
A 12-year-old girl is a newly diagnosed with a Burkitt’s lymphoma without treatment yet. She presents to the ER with decreased urine output, serum creatinine 1.9 mg/dL, uric acid 11mg/dL, potassium 6.2mg/dL, phosphorus 7.5 mg/dL. What treatment is LEAST likely to be effective at this point?
a) Hydration and Lasix, monitoring urine output and weight to maintain euvolemia
b) Alkalinization of urine with NaHCO3
c) Initiation of dialysis if diuresis does not occur
d) Recombinant uricase, such as Rasburicase
e) Allopurinol

Q. 10:
A 10-year-old boy with lymphoma has started treatment with chemotherapy. He was admitted with complains of fever for 1 day and severe right lower quadrant pain. On examination the abdomen is tender but does not have peritonitis. His white blood cell count is 0.8/mm3 with an absolute neutrophil count of 405/mm3. He is started on Imepenam. A CT scan was obtained and is shows infl ammation of the terminal ileum. There is no evidence of free air or perforation. Which of the following is the next step in management?
a) Surgical exploration
b) Add Amikacin and metrogyl
c) Continue current regime and observe
d) Start intravenous steroids
e) Do Ultrasound

Answers and rationale
Ans 1: d
With reports of late onset primary HLH in adults, older age cannot be used as a reliable criterion to exclude primary HLH. Presence or absence of infection cannot be used to distinguish primary and secondary HLH as infection is a common trigger for both instances. Soluble CD25 (ie sIL2r) ≥ 2400 U/mL is one of the eight criteria used to diagnose HLH. The main limitation of this test is that it is not easily available in ICU settings. Serum ferritin levels > 10,000 μg/L in pediatric population has a high sensitivity (>90%) and specifi city (>96%) for HLH.Hemophagocytosis on bone marrow is not pathognomic for HLH. It is often not detected at initial presentation. Serial bone marrow examinations may be required. The number of hemophagocytes on biopsy specimen do not refl ect clinical activity. Presence of hemophagocytosis is a nonspecifi c fi nding when found in isolation of other clinical features and it is important not to make treatment decision solely on the bone marrow results. There is insuffi cient data to determine which patients with secondary HLH need full treatment protocol. Clinically stable patients may improve with resolution of underlying disease or may require treatment only with steroids. However clinically unstable patients require full treatment as per HLH 2004 protocol.

Ans 2: c
Hyperleukocytosis and its associated effects due to sluggish circulation is an emergency. Leukopheresis is needed urgently. Packed RBC transfusion before leukopheresis should be avoided as it can worsen hyperviscosity and trigger the development of leukostasis. If needed, the transfusion should be administered slowly after the leukapheresis procedure. Children who are severe anemic and have congestive heart failure may be slowly transfused 3-5 ml/kg.Initiation of hyperhydration therapy in a child with Hb 5 g/dl can precipitate congestive heart failure. Additionally, diuretics may also lead to increased blood viscosity and should be delayed until the WBC count is decreased. Steroids before leukoreduction has the potential of triggering a massive tumor lysis. Mannitol will cause osmotic diuresis and worsen hyperviscosity. Moreover, it is not needed in this patient.

Ans 3: d
This patient likely has leukemia with evidence of leukostasis (respiratory and neurological manifestations). Given her already increased blood viscosity due to circulating blasts, pRBC transfusion is generally contraindicated as it can exacerbate leukostasis leading to further capillary plugging, localized ischemia, and worsening respiratory/ neurological status. Steroids, hydroxyurea, and fl uid may all be indicated (although decisions regarding induction chemotherapy and hydroxyurea should obviously be made in close consultation with hematology/oncology).

Ans 4: e
The risk of intracranial hemorrhage following leukapheresis is greatest after the WBC count has been greatly reduced (perhaps indicating risk of reperfusion injury). Hence, platelets are generally indicated to keep platelet counts >20-30000/mm3 to mitigate the risk of intracranial hemorrhage.

Ans 5: d
Rasburicase and allopurinol combination therapy is not used. A high urine pH (urine alkalinization) solubilizes uric acid, however it can cause calcium phosphate crystallization and nephropathy. Asymptomatic hypocalcemia is not treated with calcium gluconate. Phosphate removal is best achieved by CRRT in established TLS. Alkalinization of the urine using sodium bicarbonate therapy to target a urine pH>6.5 has been used to prevent urate nephropathy (as uric acid precipitates at low urine pH). However, a high urine pH also favors calciumphosphate crystallization and nephropathy. Hence, with the increased use of rasburicase to control uric acid levels, urine alkalinzation is less frequently used.

Ans 6: c
The urinary myoglobin is low, which also suggests that there is no rhabdomyolysis. The urinary haemoglobin is high, which demonstrate that there is intravascular haemolysis.

Ans 7: b
The correct answer is B because both TRALI and TACO exhibit similar symptoms initially with decreases in oxygen saturation and bilateral infi ltrates on x-ray. However, TACO responds well to diuretics whereas TRALI patients do not thus choice D is incorrect. TACO is a cardiogenic pulmonary edema whereas TRALI is non-cardiogenic, thus choice A is incorrect. TRALI is an antibody mediated process in some cases whereas TACO is a non-immune process altogether hence choice C is incorrect. Finally, choice E is incorrect because despite the rarity (likely due to under-reporting/ diagnosing of TRALI and TACO) the symptoms occur much closer to the transfusion, any time immediately after the transfusion-to- during the transfusion, and up to 6 hours post transfusion (12 hours is too far out from transfusion).

Ans 8: b
Ans 9: b

Alkalinization of the urine using sodium bicarbonate therapy to target a urine pH>6.5 has been used to prevent urate nephropathy (as uric acid precipitates at low urine pH). However, a high urine pH also favors calcium-phosphate crystallization and nephropathy. Hence, with the increased use of rasburicase to control uric acid levels, urine alkalinzation is less frequently used.

Ans 10: c
This question is about Typhlitis or Neutropenic Enterocolitis. In patients without complicated typhlitis (ie, peritonitis, perforation, or severe bleeding), nonsurgical management with bowel rest, nasogastric suction, intravenous fl uids, nutritional support, blood product support (packed red blood cells and fresh frozen plasma as needed), and broad-spectrum antibiotics is a reasonable initial approach. Examples of appropriate antimicrobial regimens include piperacillintazobactam as monotherapy or combination therapy with cefepime or ceftazidime plus metronidazole. Antibiotic coverage for C. diffi cile should be added if pseudomembranous colitis has not been excluded. An attempt to accelerate leukocyte recovery with granulocyte colony-stimulating factor (G-CSF) is reasonable, since normalization of the leukocyte count may permit containment and healing of bowel lesions. If surgery is performed, a two-stage right hemicolectomy is the preferred approach, and further chemotherapy should be delayed until recovery.