Hemophagocytic lymphohistiocytosis associated with cytomegalovirus infection in an immunocompetent infant: a diagnostic and therapeutic challenge!

Pulmonary cytomegalovirus infection: A case report and systematic review

BACKGROUND

Cytomegalovirus (CMV) is a common virus that can cause the first infection in childhood or adolescence and reactivate later in life due to immunosuppression. CMV pneumonia is a rare illness in immunocompetent patients but is one of the most significant opportunistic infections in immunocompromised patients.

AIM

To report a case and review published cases of pulmonary CMV infection in both immunocompromised and immunocompetent patients.

METHODS

We conducted a systematic search on the MEDLINE (PubMed) database, without date or language restrictions, to identify relevant studies using Medical Subject Headings and Health Science Descriptors. We manually searched the reference lists of the included studies. Simple descriptive analysis was used to summarize the results.

RESULTS

Our search identified 445 references, and after screening, 43 studies reporting 45 cases were included in the final analysis, with 29 (64%) patients being immunocompromised and 16 (36%) being immunocompetent. Fever (82%) and dyspnea (75%) were the most common clinical findings. Thoracic computed tomography showed bilateral ground-glass opacities, a relevant differential diagnosis for severe acute respiratory syndrome coronavirus 2 infection. The majority of patients (85%) received antiviral therapy, and 89% of patients recovered, while 9% of patients died.

CONCLUSION

CMV pneumonia should be considered as a differential diagnosis for coronavirus disease 2019 pneumonia, especially in immunocompromised patients. Clinicians should be aware of the clinical presentation, management, and outcomes of CMV pneumonia to guide appropriate treatment decisions.

Hemophagocytic lymphohistiocytosis due to Streptococcus suis in a 12-year-old girl: A case report

RATIONALE

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome that can be caused by bacterial infection. Streptococcus suis (S. suis) is a zoonotic pathogen that can cause severe disease in both pigs and humans. We report the first-ever documented case of HLH secondary to S. suis infection.

PATIENT CONCERNS

A 12-year-old girl presented with fever, rash, hepatosplenomegaly, pancytopenia, and elevated levels of ferritin and soluble CD25. Bone marrow examination revealed hemophagocytosis. Blood culture was positive for S. suis.

DIAGNOSIS

A diagnosis of hemophagocytic syndrome due to S. suis was established.

INTERVENTIONS

We treated the patient with intravenous immunoglobulin, intravenous imipenem, and supportive care.

OUTCOMES

The patient eventually showed complete recovery.

LESSONS

Inflammatory response plays an important role in S. suis infection. Aberrant inflammatory response to S. suis infection may induce HLH. This case report illustrates that early definitive diagnosis and prompt treatment is a key imperative in patients with suspected S. suis infection.

Cytomegalovirus associated severe pneumonia, multi-organ failure and Ganciclovir associated arrhythmia in immunocompetent child

Cytomegalovirus (CMV) can rarely cause severe manifestations in immunocompetent individuals. Hereby, we report a twelve-year-old boy who presented with tachycardia, tachypnea, fever and leukocytosis, which progressed to hypoxemic respiratory failure and severe acute respiratory distress syndrome (ARDS). Subsequently, he developed multi-organ failure despite the ongoing full supportive care and empiric broad spectrum antibiotics. Cytomegalovirus infection was diagnosed by Polymerase Chain Reaction (PCR) in blood and histopathological examination of lung biopsy. Immunological work up for the child was unremarkable. Ganciclovir therapy was introduced and showed significant improvement until full recovery. However, our patient developed transient heart block as a rare complication for Ganciclovir therapy throughout his course. We present this case with literature review for the CMV infection associated morbidity and mortality among immunocompetent children.

Secondary haemophagocytic lymphohistiocytosis triggered by postnatally acquired cytomegalovirus infection in a late preterm infant

Haemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory condition with impairment of cytotoxic T-cells and natural killer cells. Causes in infants are mostly hereditary immune defects as well as various infectious triggering factors, amongst these cytomegalovirus (CMV). Vertical CMV transmission may occur in utero, during birth, and by breast feeding. Usually, a CMV infection transmitted via breast milk is symptomatic only in very immature preterm infants. We report on a late preterm infant born after 35 + 5 weeks of gestation with a birth weight of 1840 g, being admitted to our intensive care unit at the age of 9 weeks with acute enteritis and severe dehydration. After a prolonged recovery, the infant developed a sepsis-like condition with hyperpyrexia, hepatosplenomegaly, and pancytopenia. Combination with high ferritin levels (2809 μg/l), hypertriglyceridaemia (481 mg/dl), elevated soluble IL-2 receptor (sCD25, 9120 U/ml), and reduced perforin expression allowed diagnosis of HLH, caused by an acute CMV infection. Since connatal CMV infection had been ruled out earlier, we report the rare case of secondary HLH triggered by a postnatally acquired symptomatic CMV infection in an immunocompetent infant, most likely transmitted via breast milk. The infant was successfully treated with ganciclovir without need for immunosuppressive therapy.

Hemophagocytic lymphohistiocytosis in a patient with Sjögren's syndrome: case report and review

Hemophagocytic lymphohistiocytosis (HLH) is a very rare syndrome with a mortality up to 95% of cases if not treated. It is characterised by an excessive activation of the immune system that leads to a disproportionate and destructive inflammatory response. The high mortality rates are in part due to a delay in the diagnosis, and therefore clinicians must maintain a high index of suspicion. When the treatment is started early, the survival rate reaches around 55% of cases. HLH usually presents with persistent fever, pancytopenia, and organomegaly and is associated with very high levels of serum ferritin. In this manuscript, we present the case of a patient with primary Sjögren's syndrome who developed HLH after an acute infection by Cytomegalovirus. We will describe and discuss the pathogenesis, differential diagnosis and a pragmatic approach to the treatment for this critically important and, when diagnosed early, potentially curable syndrome.