PATIENT WITH ONCOLOGICAL CONDITONS - NEUTROPENIC FEVER and TUMOR LYSIS SYNDROME

 

NEUTROPENIC FEVER

Neutropenia arises mostly from treatment of malignancy by chemotherapy, and is defined by absolute neutrophil counts of less than 1500 (1000-1500: mild, 500-999: moderate, <500: severe). The most common organisms are gram positive cocci like coagulase-negative staphylococci, viridians streptococci, and staphylococci aureus and gram negative organisms like Escherichia coli, Klebsiella species, and Pseudomonas aeruginosa. Factors which may increase a patient’s risk of developing neutropenic fever include intravenous devices, high-dose chemotherapy regimens, corticosteroid use, mucositis and bone marrow incompetence

PRESENTATION AND DIAGNOSIS

Patients present with a temperature of more than 38 degree celcius, and may often not having localizing symptoms of infection, partially due to the lack of an inflammatory response. A full physical examination to try to elucidate the source of infection should be performed, taking care to avoid invasive procedures where possible e.g. urinary catheterization, digital rectal examination, vaginal examination, lumbar puncture or chest tube insertion. A full septic workup should be performed, taking specimens for culture from the blood, urine and other relevant sources e.g. from sputum, stool or wounds. Maintenance of good hygiene should be maintained.

MANAGEMENT

Neutropenic patients should ideally be managed in a hospital. Intravenous antibiotics which are active against both gram-positive cocci and gram-negative bacilli should be commenced as soon as possible. Current local guidelines suggest a broad spectrum cephalosporin like  cefepime as the first-line antibiotic, with other options being ceftriaxone/gentamicin, ceftazidime or piperacillin/tazobactam. Ciprofloxacin, aztreonam and vancomycin can be considered in patients hypersensitive to pencillins. In patients with suspected central line infections, vancomycin should be added, and persistent infections may necessitate removal of the line. Where fever is persistent and fungal infection is suspected, amphotericin may be considered.

TUMOR LYSIS SYNDROME

This syndrome is due to the effects of treatment of the malignancy. There is a reaction to the sudden and large release of cellular lysis products caused by tumor destruction. The body may be unable to excrete and neutralize such toxic products

PRESENTATION AND DIAGNOSIS

It usually presents within 1 to 5 days of chemotherapy or radiation. It commonly develops in high-grade lymphomas, leukemia, and any other rapidly-proliferating tumor with a large tumor burden. An increased pre-treatment uric acid or lactate dehydrogenase level, pre-existing renal insufficiency or hypovolaemia increases the risk of occurrence. In tumor lysis syndrome, the following metabolic abnormalities occur: hyperuricaemia, hyperkalaemia, hyperphosphataemia, hypocalcaemia and acute renal failure.

MANAGEMENT

Those at risk should have preventive management by receiving intravenous hydration with normal saline 3-6 liter/24hours, with sodium bicarbonate. Acetazolamide is used to alkalinize the urine and prophylactic allopurinol is given. Diuresis with furosemide or mannitol is used with careful monitoring of electrolyte levels and maintenance of fluid balance. Hyperphosphataemia is treated with oral aluminum hydroxide. Hyperkalaemia and hypocalcaemia are treated accordingly, while severe acute renal failure or refractory hyperkalaemia can be managed with dialysis if necessary. 

PATIENT WITH ONCOLOGICAL CONDITONS - NEUTROPENIC FEVER and TUMOR LYSIS SYNDROME