The Link between Iron Turnover and Pharmacotherapy in Transplant Patients

Iron is a transition metal that plays a crucial role in several physiological processes. It can also exhibit toxic effects on cells, due to its role in the formation of free radicals. Iron deficiency and anemia, as well as iron overload, are the result of impaired iron metabolism, in which a number of proteins, such as hepcidin, hemojuvelin and transferrin, take part. Iron deficiency is common in individuals with renal and cardiac transplants, while iron overload is more common in patients with hepatic transplantation. The current knowledge about iron metabolism in lung graft recipients and donors is limited. The problem is even more complex when we consider the fact that iron metabolism may be also driven by certain drugs used by graft recipients and donors. In this work, we overview the available literature reports on iron turnover in the human body, with particular emphasis on transplant patients, and we also attempt to assess the drugs’ impact on iron metabolism, which may be useful in perioperative treatment in transplantology.

Trimethoprim–Sulfamethoxazole: new lessons on an old antimicrobial; a retrospective analysis

Objective

This study aimed to evaluate the appropriateness of TMP-SMX prescriptions as part of drug utilization review.

Method

Charts of all patients (adults and paediatrics) admitted to Hamad General Hospital who received TMP-SMX from December 2016 till May 2017 were reviewed and assessed for prescribing/administering appropriateness.

Key findings

Total of 149 patients was included (55 paediatrics, 94 adults). None of the adults were tested for G6PD before initiating TMP-SMX, while most of the paediatrics (85.5%) had a record of G6PD status. Dosing of TMP-SMX was considered appropriate in 65% of the paediatrics, whereas only in 49% of adults. Bone infections and S. maltophilia were the uppermost indications associated with inappropriate dosing (85.7 and 74.3%, respectively). Errors in dosing were observed to be higher with intravenous formulations (51.2%) compared to orals (35.2%). With regard to pharmacy verification/dispensing, 135 out of 149 orders (90.6%) were correctly verified/dispensed. Appropriateness of the prescribed dosing was only significantly affected by the indication for TMP-SMX use (P-value < 0.001), while the route of administration was the only variable that correlated significantly with pharmacy verification/dispensing errors (P-value 0.032).

Conclusion

TMP-SMX prescribing patterns were not always optimum. The results of this study should promote healthcare facilities to review/ensure optimal utilization of TMP-SMX which can consequently help in diminishing burden of antimicrobial resistance.

Use of trimethoprim-sulfamethoxazole in a patient with G6PD deficiency for treating Pneumocystis jirovecii pneumonia without haemolysis: Case report and literature review

WHAT IS KNOWN AND OBJECTIVE

A fixed dose of trimethoprim-sulphamethoxazole (TMP/SMZ) is the first-line therapy for Pneumocystis jirovecii pneumonia (PJP). Other alternative regiments have shown a suboptimal cure rate. However, TMP/SMZ has been reported to cause haemolyses when administered to patients with G6DP deficiency. PJP might be fatal without treatment. To date, there is still insufficient evidence to manage PJP with TMP/SMZ in G6DP deficiency population.

CASE DESCRIPTION

We report a G6PD-deficient patient with human immunodeficiency virus (HIV) and PJP infection treated successfully with 21 days of high dose TMP/SMZ without any signs and symptoms of haemolysis.

WHAT IS NEW AND CONCLUSION

Based on our experience, it is worth to note that despite TMP/SMZ is consider unsafe in patient with pre-existing G6PD-deficiency, it could still be suggested as the initial drug of choice in Taiwanese or southeast Asian population for treating PJP infected HIV patient.

Drug-induced meningitis: A review of the literature and comparison with an historical cohort of viral meningitis cases

BACKGROUND

Drug-induced aseptic meningitis (DIAM) is potentially insufficiently considered by clinician, being of rare etiology, with there being no previously published exhaustive study describing its clinical and biological features.

METHODS

Two independent academic clinicians searched all the case reports of DIAM from 1995 until 15^th April, 2017. The search was limited to studies performed in humans, published in English or French. Clinical and biological data of subjects were compared with those of patients with documented viral meningitis.

RESULTS

One hundred and fifty-one case reports fulfilled our inclusion criteria. Non-steroidal anti-inflammatory drugs were the commonest drug cause of AM n=49, followed by antibiotics n=46, biotherapy n=19 and finally immunomodulators n=15. The clinical and biological presentation of DIAM varies according to the causative etiological drug, especially with respect to the interval between exposure and presentation and cerebrospinal fluid (CSF) pleiocytosis. Clinical symptoms associated with meningitis were more prevalent in viral meningitis than in DIAM, except for fever and signs of encephalitis. Cerebrospinal fluid examination in DIAM reveals an increased CSF white cell count and an increased proportion of neutrophils and protein, compared with viral meningitis.

DISCUSSION

We present an extensive review of the DIAM case reports, and highlight their clinical and biological characteristics according to the drugs involved. While comparing for the first time their characteristics with those of viral meningitis, this review hopes in facilitate earlier diagnosis and management of DIAM in clinical practice.

The first reported case of concurrent trimethoprim-sulfamethoxazole-induced immune hemolytic anemia and thrombocytopenia

BACKGROUND

Drug-induced immune hemolytic anemia (DIIHA) and drug-induced immune thrombocytopenia (DIIT) are rare but dangerous complications of pharmacotherapy that may be underrecognized in hematopoietic stem cell transplant (HSCT) patients due to overlap of signs and symptoms with those of more common disease processes.

CASE REPORT

A 61-year-old woman with NK-cell deficiency and GATA-2-associated myelodysplastic syndrome, status post-recent allogeneic HSCT (Day +58), presented with 3 days of acute-onset severe back pain, muscle cramps, and increasingly dark urine. She was found to be anemic, thrombocytopenic, and in acute renal failure. On admission, the direct antiglobulin test was positive for complement (C3) only. After careful review of her medication list, the possibility of DIIHA was raised. She had started taking trimethoprim-sulfamethoxazole (TMP-SMX) for Pneumocystis jiroveci pneumonia prophylaxis 24 days prior on a weekend dose schedule. Serologic tests on peripheral blood samples were performed using standard methods. Drug studies were performed at an immunohematology reference laboratory.

RESULTS

The patient's serum showed hemolysis of donor red blood cells in the presence of TMP-SMX and also TMP-SMX-induced platelet antibodies. The patient was treated with transfusions, hemodialysis, and immunosuppressive agents. Her clinical condition improved and she was discharged after 8 days in stable condition.

CONCLUSION

This case describes the first reported concurrent DIIHA and DIIT due to TMP-SMX-induced antibodies in an HSCT patient. DIIHA and DIIT can present a diagnostic challenge in the setting of intermittent medication dosing.

Trimethoprim-sulfamethoxazole-induced aseptic meningitis-not just another sulfa allergy

OBJECTIVE

To review the literature on trimethoprim-sulfamethoxazole (TMP-SMX)-induced aseptic meningitis (TSIAM) and discuss the features, possible mechanisms, evaluation, and treatment options relevant for the allergist.

DATA SOURCES

A MEDLINE search was performed using the terms aseptic meningitis, trimethoprim-sulfamethoxazole, trimethoprim, and sulfamethoxazole.

STUDY SELECTIONS

Cases were included that fit the case definition of headache, neck pain, or change in mental status with elevated cerebrospinal fluid white blood cell count or protein attributable to TMP-SMX or either medication alone.

RESULTS

Forty-one patient cases were reviewed. There was a predominance of female patients and patients with autoimmune disease reported. Fever, headache, neck pain, and altered mental status were the most common findings reported in TSIAM reactions. Severe reactions ranged from hypotension to seizure and unconsciousness or coma. Typical cerebrospinal fluid findings included elevated white blood cell count with neutrophil predominance, elevated protein, and normal glucose. Symptoms quickly remitted with withdrawal of TMP-SMX, typically over 48 to 72 hours. Full recovery was typically experienced, although permanent paraplegia was reported in 1 case. The mechanism of reaction is unknown, although an IgE-mediated reaction is unlikely. Many patients experienced multiple TSIAM reactions before the diagnosis was made. Diagnosis can be confirmed with drug challenge or graded test dosing when necessary. Patients with TSIAM subsequently reacted to TMP and SMX alone and therefore should be advised to avoid these 2 classes of medication after diagnosis.

CONCLUSION

TMP-SMX is the most common antibiotic to cause drug-induced aseptic meningitis. By being aware of this reaction, allergists are well poised to diagnose TSIAM and prevent future reoccurrences for the patient.

Cotrimoxazole - optimal dosing in the critically ill

The optimum dosage regimen for cotrimoxazole in the treatment of life threatening infections due to susceptible organisms encountered in critically ill patients is unclear despite decades of the drug's use. Therapeutic drug monitoring to determine the appropriate dosing for successful infection eradication is not widely available. The clinician must utilize published pharmacokinetic, pharmacodynamic, and effective inhibitory concentration information to determine potential dosing regimens for individual patients when treating specific pathogens. Using minimum inhibitory concentrations known to successfully block growth for target pathogens, the pharmacokinetics of both trimethoprim and sulfamethoxazole can be utilized to establish empiric dosing regimens for critically ill patients while considering organ of clearance impairment. The author's recommendations for appropriate dosing regimens are forwarded based on these parameters.

Haemolytic anaemia and renal failure associated with antibodies to trimethoprim and sulfamethoxazole

AIM

The aim of this study was to support a clinical diagnosis of drug-induced immune haemolytic anaemia (DIIHA).

BACKGROUND

DIIHA is rare and has only been described twice with the antibiotic combination of trimethoprim (TMP) and sulfamethoxazole (SMX).

METHODS/MATERIALS

Serologic tests for drug antibodies were performed using methods previously published by our laboratory.

RESULTS

A 44-year-old woman experienced body aches, chills, chest pressure, nausea and a rash while receiving TMP-SMX; a week later her haemoglobin was low and she was in renal failure. At the hospital, the direct antiglobulin test (DAT) was positive (C3 only) and the serum reacted with all red blood cells (RBCs) by the gel method only (TMP-SMX is present in the RBC diluent used for the gel method). At the Red Cross immunohaematology laboratory, the patient's serum was reactive in the presence of TMP-SMX (haemolysis and positive antiglobulin test), pure TMP (positive antiglobulin test using anti-IgG only) and pure SMX (haemolysis and positive antiglobulin test using both anti-IgG and anti-C3). The patient was treated with transfusions and haemodialysis and was discharged after a week in stable condition.

CONCLUSION

We describe a patient who appeared to have haemolytic anaemia and renal failure associated with antibodies to both TMP and SMX.