Case 1
A 2-year-old girl from Weining, Guizhou, China, presented in July 2017 with a repeated irregular fever lasting 3 months and reaching 39°C–40°C. After the illness, she was hospitalized at a local hospital for 2 months. Her whole blood cells decreased progressively, and she underwent symptomatic and supportive treatment, including meropenem, vancomycin, piperacillin, tazobactam, gamma globulin, methylprednisolone, cefoperazone, sulbactam, Taineng, and a blood transfusion. She continued to have repeated fevers, coughing with sputum, abdominal distension, anorexia, and fatigue. She had a history of mosquito bites and contact with a domestic dog 1 month before onset as well as a history of Epstein-Barr virus-related hemophagocytic syndrome.
Case 2
A 9-month-old girl from Zhaotong City, Yunnan Province, China, who had been living in Zhouqu County, Gansu Province, from July to September 2020 was admitted to our hospital. During this period, the infant had a history of mosquito bites that resolved after 3 months. She had diarrhea for half of December 2020, with a subsequent irregular fever lasting 1 month and reaching 39°C–40°C and decreased blood cells in the peripheral blood. She did not recover at her local hospital and was thus transferred to Kunming Children’s Hospital.
Both patients had hepatosplenomegaly, hypertriglyceridemia, and hypofibrinogenemia. Tables 1–5 show the relevant results. The results of the hemophagocytic cells in both infants’ bone marrow while at the other hospital met the HLH-2004 standard [2]. The results of the primary HPS-related genetic test were negative and ruled out congenital HPS. All results were in accordance with the HPS-2004 chemotherapy regimen [2].
According to HLH-2004 chemotherapy regimen : ① Dexamethasone: from Day 2 after admission, 10 mg/(m2 .d) for 2 weeks, 5 mg/(m2 .d) for 4 days; ② Etoposide: from Day 6 after admission, twice a week, 5 mg/kg each time, a total of 4 times; ③ Other support treatment: blood and immunoglobulin transfusion,recombinant human granulocyte stimulating factor.However, after standardized HLH-associated chemotherapy, the symptoms did not significantly disappear, and the patients still had fevers and severe infection. Both patients’ bone marrow cell morphology was re-examined at Kunming Children’s Hospital. The pathogens of Kala-azar and Leishmania amastigotes were found, along with hemophagocytic cells; thus, VL-HPS was diagnosed. However, because our hospital lacks the drugs to treat this disease, the patients were transferred to a specialty hospital. Telephone interviews confirmed that after receiving symptomatic medication at the specialty hospital, the patients’ conditions quickly improved. Both patients recovered and were discharged.
Laboratory inspection
Table 1
Basic conditions of two patients with Visceral leishmaniasis
General conditions
|
Case 1
|
Case 2
|
Age
|
2 years
|
9 months
|
Sex
|
female
|
female
|
Onset month
|
July
|
November
|
History of mosquito bites
|
Yes
|
Yes
|
Fever
|
39℃–40℃
|
39.5℃–40℃
|
Cough
|
Yes
|
No
|
Reaction
|
Poor
|
Poor
|
Course of illness
|
3 months
|
2 months
|
History of epidemiology
|
Yes
|
Yes
|
Pathogenic examination
The results of the examination for related pathogens revealed the kala-azar pathogen/Leishmania amastigotes in the bone marrow of both patients (Figs. 1 and 2).Leishmania amastigotes can be seen inside and outside of phagocytes,Its shape is round and oval, with a diameter of about 2 to 5 um,The cytoplasm is light blue, with a large round nucleus inside, and the nucleus is purplish red.Beside the nucleus, a small, rod-shaped, and darkly colored moving matrix can be seen.The morphological characteristics were consistent with those of Leishmania amastigotes. Hemophagocytic cells were easily seen in the bone marrow of both patients (Figs. 3 and 4.2). One child was infected with the Epstein-Barr virus but tested negative for other pathogens (Table 2).
Table 2
Pathogen detection in two patients with Visceral leishmaniasis
Etiological examination
|
Case 1
|
Case 2
|
Epstein-Barr virus
|
2.82E^03
|
negative
|
Cytomegalovirus
|
negative
|
negative
|
Rubella virus
|
negative
|
negative
|
Influenza virus
|
negative
|
negative
|
Respiratory syncytial virus
|
negative
|
negative
|
Adenovirus
|
negative
|
negative
|
Legionella pneumophila
|
negative
|
negative
|
Mycoplasma pneumoniae, Chlamydia
|
negative
|
negative
|
Q fever, rickettsia
|
negative
|
negative
|
Blood culture
|
negative
|
negative
|
Bone marrow cytology
|
|
|
Leishmania amastigotes
|
positive
|
positive
|
Hemophagocytic cells
|
easily seen
|
easily seen
|
Hemophagocytic-related genes
|
negative
|
negative
|
Acute and chronic leukemia immunophenotyping
|
negative
|
negative
|
Table 3. Blood routine indexes, infection indexes and biochemical results for both patients
Detection index
|
Normal range
|
On admission
|
After treatment for 14 days
|
Characteristics
|
Case 1
|
Case 2
|
Case 1
|
Case 2
|
White blood cell count,× 109/L
|
4.0–10.0
|
2.0
|
4.5
|
3.4
|
3.9
|
Red blood cell count,×1012/L)
|
4.0–5.5
|
2.0
|
3.8
|
3.3
|
3.3
|
Hemoglobin, g/L
|
97–141
|
69.0
|
94.0
|
91.0
|
97.0
|
Platelet count,× 109/L
|
100–300
|
35.0
|
44.0
|
66.0
|
28.0
|
High-sensitivitC-reactive protein(mg/L)
|
0.5–10.0
|
151.8
|
198.3
|
85.3
|
16.3
|
Procalcitonin (ng/ml)
|
0-0.25
|
5.4
|
2.3
|
3.5
|
1.8
|
Ferritin (µg/L)
|
7.0-142.0
|
40000.0
|
69445.0
|
1886.0
|
2000.0
|
Fibrinogen (g/L)
|
2.0–4.0
|
1.2
|
0.9
|
1.1
|
1.4
|
Alanine aminotransferase (U/L)
|
0–40.0
|
75.0
|
178.0
|
41.0
|
149.0
|
Total protein (g/L)
|
55.0–76.0
|
62.2
|
55.7
|
62.2
|
65.1
|
Albumin (g/L)
|
39.0–54.0
|
24.7
|
29.2
|
24.7
|
30.9
|
Globulin (g/L)
|
12.0–34.0
|
37.5
|
36.5
|
37.5
|
34.2
|
Lactate dehydrogenase (U/L)
|
109.0-245.0
|
2700.0
|
2648.0
|
256.0
|
1803.8
|
Triglycerides (mmol/L)
|
1.70–2.30
|
4.2
|
4.5
|
2.0
|
2.5
|
Routine blood test, infection index and biochemical examination resultsdecreased significantly but remained higher than the normal reference range. Alanine aminotransferase, lactate dehydrogenase and α-hydroxybutyric acid were increased, and albumin was decreased in both children (Table 3).Both children had reductions in whole blood cells or in two lines before treatment. The infection indicators (i.e., high-sensitivity C-reactive protein, procalcitonin, and ferritin) were significantly increased, and fibrinogen was significantly reduced. After 14 days of treatment per the HLH-2004 chemotherapy regimen, their routine blood indexes changed little, and their infection indexes